Update wordpress monorepo (#2929)

* Update wordpress monorepo

* Add missing Gutenberg grid variables

* Fix button styling

* Fix snapshots (new classes and events are passed through from WP components update)

* Adjust button overwrites

* Update package-lock.json

* Fix focus issues/conflicts with react-dates and Dropdown

* Maintain DateRange focus without impacting expected "click outside" behavior.

* Resolve multiple React versions, update testing dependencies.

* blow away package-lock.json and refresh

- this fixed tests after an npm install on my end

* Allow tabbing to month nav and calendar grid.

* Fix keyboard navigation of DayPicker elements.

Add prop for specifying an element that's allowed to take focus from DateRange.

* refresh package-lock

client/header/activity-panel/activity-card/style.scss

@@ -110,10 +110,6 @@
 	& > * + * {
 		margin-left: 0.5em;
 	}
-
-	a.components-button.is-button {
-		color: $gray-text;
-	}
 }
 
 .woocommerce-activity-card.is-loading {

client/stylesheets/abstracts/_colors.scss

@@ -28,6 +28,9 @@ $gray-text: $core-grey-dark-500;
 
 // Gutenberg
 $button-hover: #fafafa;
+$button-hover-border: #999;
+$button-disabled: #a0a5aa;
+$button-disabled-border: #ddd;
 $button-focus-inner: #00435d;
 $button-focus-outer: #bfe7f3;
 $input-active-border: #00a0d2;

client/stylesheets/abstracts/_variables.scss

@@ -74,6 +74,10 @@ $toggle-border-width: 2px;
 $radius-round-rectangle: 4px;
 $icon-button-size: 36px;
 $icon-button-size-small: 24px;
+$grid-size-small: 4px;
+$grid-size: 8px;
+$grid-size-large: 16px;
+$grid-size-xlarge: 24px;
 
 // Newspack variables. These are temporary until we move away from Newspack components.
 $muriel-white: $studio-white;

client/stylesheets/shared/_global.scss

@@ -56,16 +56,48 @@
 
 	.components-button.is-button.is-primary {
 		color: $studio-white;
+		box-shadow: none;
 
 		&:not(:disabled) {
 			&:hover,
 			&:active,
 			&:focus {
+				box-shadow: none;
 				color: $studio-white;
 			}
 		}
 	}
 
+	.components-button.is-button.is-default {
+		color: $gray-text;
+		border-color: $button-border;
+		background: $button;
+		box-shadow: none;
+
+		&:not(:disabled) {
+			&:hover,
+			&:active,
+			&:focus {
+				color: $gray-text;
+				background: $button-hover;
+				border-color: $button-hover-border;
+			}
+		}
+	}
+
+	.components-button.is-default:disabled {
+		color: $button-disabled;
+		border-color: $button-disabled-border;
+		background: $button;
+		&:hover,
+		&:active,
+		&:focus {
+			color: $button-disabled;
+			border-color: $button-disabled-border;
+			background: $button;
+		}
+	}
+
 	input:focus,
 	select:focus,
 	button:focus {