Remove outline from tour highlight and tweak border color

[donnapep]

Proposed Changes

This PR removes the outline for the Sensei tour, as it was a bit too harsh and didn't enable the box shadow to truly stand out. It also removes the hard-coded color for classic themes and block themes that don't have a primary color defined, and uses currentcolor instead to better blend with the theme.

Before

After

Testing Instructions

1. Take the course tour and ensure there is no outline on the focused element and that the outline color looks good.
2. Test on different themes.

Pre-Merge Checklist

• PR title and description contain sufficient detail and accurately describe the changes
• Acceptance criteria is met
• Decisions are publicly documented
• Adheres to coding standards (PHP, JavaScript, CSS, HTML)
• All strings are translatable (without concatenation, handles plurals)
• Follows our naming conventions (P6rkRX-4oA-p2)
• Hooks (p6rkRX-1uS-p2) and functions are documented
• New UIs are responsive and use a mobile-first approach
• New UIs match the designs
• Different user privileges (admin, teacher, subscriber) are tested as appropriate
• Legacy courses (course without blocks) are tested
• Code is tested on the minimum supported PHP and WordPress versions
• User interface changes have been tested on the latest versions of Chrome, Firefox and Safari
• "Needs Documentation" label is added if this change requires updates to documentation
• Known issues are created as new GitHub issues

[github-actions]

Test the previous changes of this PR with WordPress Playground.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 51.82%. Comparing base (4e9c1a4) to head (b27f20c).
Report is 1 commits behind head on trunk.

Additional details and impacted files

@@            Coverage Diff            @@
##              trunk    #7548   +/-   ##
=========================================
  Coverage     51.82%   51.82%           
  Complexity    11307    11307           
=========================================
  Files           640      640           
  Lines         47979    47979           
  Branches        446      446           
=========================================
  Hits          24865    24865           
  Misses        22755    22755           
  Partials        359      359           

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[github-actions]

Test the previous changes of this PR with WordPress Playground.

[github-actions]

Test the previous changes of this PR with WordPress Playground.

[m1r0]

Looks good. 👍

[Imran92]

Looks cleeeeean <3