Make back link arrow consistent with breadcrumb component

[vanitabarrett]

What

This PR contains a few small changes to the back link component:

• updates the back link arrow to be consistent with the breadcrumbs component
• increase the touch target of the back link

Note: this change has been implemented on GOVUK and we wish to contribute this change back to the design system.

Why

• Back links use an inconsistent icon from the breadcrumbs and there should be consistent design patterns across GOV.UK.
• The touch target of the back link should be a minimum of 44x44px as recommended by WCAG guidelines
• The touch target has been implemented regardless of device to handle people interacting with the link, for example, on touchscreen laptops.

Before

After

[timpaul]

For reference, this change has been requested before via our backlog.

[christopherthomasdesign]

Just noticed a small inconsistency with the breadcrumb chevron colour. Maybe that's deliberate but can't think of a reason they should be different. Otherwise all looks good 👍

[christopherthomasdesign]

Checked out locally, looks great to me 👍thanks!

[36degrees]

Something slightly strange going on with the changelog – seeing duplicated entries for two unrelated changes. @vanitabarrett are you able to take a look?

[vanitabarrett]

Oops, probably a rebase issue. I'll look into it

[vanitabarrett]

@36degrees Fixed 👍

[36degrees]

Thanks, @vanitabarrett 👏