Fix: Shopping Button default hover and focus style

[dinhtungdu]

Follows up #6130

This PR adds the default hover and focus style for the Shopping Button. This fixes the issue that the button disappears on hover/focus when only the background color is set.

Screenshots

Before
After

Testing

Automated Tests

• Changes in this PR are covered by Automated Tests.
  • Unit tests
  • E2E tests

Manual Testing

How to test the changes in this Pull Request:

1. Edit the Mini Cart Contents block.
2. Set only the background color.
3. On the front end, hover over the Start shopping button.
4. See the button is still visible, with black background and border.

User Facing Testing

These are steps for user testing (where "user" is someone interacting with this change that is not editing any code).

• Same as above, or
• See steps below.

[github-actions]

Size Change: +101 B (0%)

Total Size: 862 kB

Filename	Size	Change
build/wc-blocks-style-rtl.css	22.3 kB	+53 B (0%)
build/wc-blocks-style.css	22.3 kB	+48 B (0%)

ℹ️ View Unchanged

Filename	Size
build/active-filters-frontend.js	5.92 kB
build/active-filters.js	6.96 kB
build/all-products-frontend.js	18.2 kB
build/all-products.js	33.9 kB
build/all-reviews.js	8.02 kB
build/attribute-filter-frontend.js	16.9 kB
build/attribute-filter.js	13.1 kB
build/blocks-checkout.js	17.4 kB
build/cart-blocks/accepted-payment-methods-frontend.js	1.17 kB
build/cart-blocks/checkout-button-frontend.js	1.15 kB
build/cart-blocks/empty-cart-frontend.js	346 B
build/cart-blocks/express-payment-frontend.js	5.19 kB
build/cart-blocks/filled-cart-frontend.js	757 B
build/cart-blocks/items-frontend.js	300 B
build/cart-blocks/line-items-frontend.js	5.5 kB
build/cart-blocks/order-summary-frontend.js	8.87 kB
build/cart-blocks/totals-frontend.js	320 B
build/cart-frontend.js	45 kB
build/cart.js	43.6 kB
build/checkout-blocks/actions-frontend.js	1.41 kB
build/checkout-blocks/billing-address--checkout-blocks/shipping-address-frontend.js	4.12 kB
build/checkout-blocks/billing-address-frontend.js	891 B
build/checkout-blocks/contact-information-frontend.js	2.83 kB
build/checkout-blocks/express-payment-frontend.js	5.49 kB
build/checkout-blocks/fields-frontend.js	344 B
build/checkout-blocks/order-note-frontend.js	1.07 kB
build/checkout-blocks/order-summary-frontend.js	11.3 kB
build/checkout-blocks/payment-frontend.js	7.77 kB
build/checkout-blocks/shipping-address-frontend.js	998 B
build/checkout-blocks/shipping-methods-frontend.js	4.74 kB
build/checkout-blocks/terms-frontend.js	1.22 kB
build/checkout-blocks/totals-frontend.js	325 B
build/checkout-frontend.js	47.2 kB
build/checkout.js	44.7 kB
build/featured-category.js	8.61 kB
build/featured-product.js	9.71 kB
build/handpicked-products.js	7.09 kB
build/legacy-template.js	2.19 kB
build/mini-cart-component-frontend.js	16.5 kB
build/mini-cart-contents-block/empty-cart-frontend.js	329 B
build/mini-cart-contents-block/filled-cart-frontend.js	230 B
build/mini-cart-contents-block/footer--mini-cart-contents-block/products-table-frontend.js	5.32 kB
build/mini-cart-contents-block/footer-frontend.js	5.63 kB
build/mini-cart-contents-block/items-frontend.js	226 B
build/mini-cart-contents-block/products-table-frontend.js	5.36 kB
build/mini-cart-contents-block/shopping-button-frontend.js	287 B
build/mini-cart-contents-block/title-frontend.js	367 B
build/mini-cart-contents.js	23.3 kB
build/mini-cart-frontend.js	1.72 kB
build/mini-cart.js	6.56 kB
build/price-filter-frontend.js	12.1 kB
build/price-filter.js	8.49 kB
build/price-format.js	1.19 kB
build/product-add-to-cart--product-button--product-category-list--product-image--product-price--product-r--a0326d00.js	224 B
build/product-add-to-cart--product-button--product-image--product-title.js	2.64 kB
build/product-add-to-cart-frontend.js	7 kB
build/product-add-to-cart.js	7.47 kB
build/product-best-sellers.js	7.37 kB
build/product-button--product-category-list--product-image--product-price--product-rating--product-sale-b--e17c7c01.js	499 B
build/product-button-frontend.js	2.08 kB
build/product-button.js	2.29 kB
build/product-categories.js	3.17 kB
build/product-category-list-frontend.js	923 B
build/product-category-list.js	499 B
build/product-category.js	8.47 kB
build/product-image-frontend.js	1.85 kB
build/product-image.js	1.08 kB
build/product-new.js	7.67 kB
build/product-on-sale.js	7.98 kB
build/product-price-frontend.js	1.93 kB
build/product-price.js	1.51 kB
build/product-rating-frontend.js	1.15 kB
build/product-rating.js	731 B
build/product-sale-badge-frontend.js	1.09 kB
build/product-sale-badge.js	681 B
build/product-search.js	2.18 kB
build/product-sku-frontend.js	380 B
build/product-sku.js	382 B
build/product-stock-indicator-frontend.js	1.03 kB
build/product-stock-indicator.js	621 B
build/product-summary-frontend.js	1.33 kB
build/product-summary.js	917 B
build/product-tag-list-frontend.js	917 B
build/product-tag-list.js	494 B
build/product-tag.js	7.81 kB
build/product-title-frontend.js	1.28 kB
build/product-title.js	902 B
build/product-top-rated.js	7.9 kB
build/products-by-attribute.js	8.38 kB
build/reviews-by-category.js	11.4 kB
build/reviews-by-product.js	12.6 kB
build/reviews-frontend.js	6.97 kB
build/single-product-frontend.js	21.6 kB
build/single-product.js	10 kB
build/stock-filter-frontend.js	6.5 kB
build/stock-filter.js	6.57 kB
build/vendors--cart-blocks/line-items--cart-blocks/order-summary--checkout-blocks/order-summary--checkout--6efbf40e-frontend.js	5.26 kB
build/vendors--cart-blocks/line-items--checkout-blocks/order-summary--mini-cart-contents-block/products-table-frontend.js	3.14 kB
build/vendors--cart-blocks/order-summary--checkout-blocks/billing-address--checkout-blocks/order-summary---4f3822fa-frontend.js	19.3 kB
build/vendors--cart-blocks/order-summary--checkout-blocks/billing-address--checkout-blocks/order-summary---eb4d2cec-frontend.js	4.74 kB
build/vendors--mini-cart-contents-block/footer--mini-cart-contents-block/products-table-frontend.js	7.35 kB
build/vendors--product-add-to-cart-frontend.js	7.54 kB
build/wc-blocks-data.js	9.83 kB
build/wc-blocks-editor-style-rtl.css	4.87 kB
build/wc-blocks-editor-style.css	4.87 kB
build/wc-blocks-google-analytics.js	1.56 kB
build/wc-blocks-middleware.js	930 B
build/wc-blocks-registry.js	2.7 kB
build/wc-blocks-shared-context.js	1.52 kB
build/wc-blocks-shared-hocs.js	1.14 kB
build/wc-blocks-vendors-style-rtl.css	1.28 kB
build/wc-blocks-vendors-style.css	1.28 kB
build/wc-blocks-vendors.js	70.7 kB
build/wc-blocks.js	2.62 kB
build/wc-payment-method-bacs.js	816 B
build/wc-payment-method-cheque.js	811 B
build/wc-payment-method-cod.js	909 B
build/wc-payment-method-paypal.js	837 B
build/wc-settings.js	2.61 kB

_{compressed-size-action}

[Aljullu]

LGTM