Issue / 9864 Update Icons to Inherit Color

[10upsimon]

Summary

Addresses issue:

• Update all icons to inherit color #9864

Relevant technical choices

• Updated all SVG files, removed fill and stroke color definitions (where applicable) and changed to currentColor.
• Updated CSS rules across the codebase and correctly defined color properties in order for SVG icons to inherit the correct color.
• Explicitly updated the VRT reference images for SubtleNotification custom icon story, as the incorrect shade of green was being used prior. The icon now correctly inherits the same green color as defined for the banner itself.

PR Author Checklist

• My code is tested and passes existing unit tests.
• My code has an appropriate set of unit tests which all pass.
• My code is backward-compatible with WordPress 5.2 and PHP 7.4.
• My code follows the WordPress coding standards.
• My code has proper inline documentation.
• I have added a QA Brief on the issue linked above.
• I have signed the Contributor License Agreement (see https://cla.developers.google.com/).

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Code Reviewer Checklist

• Run the code.
• Ensure the acceptance criteria are satisfied.
• Reassess the implementation with the IB.
• Ensure no unrelated changes are included.
• Ensure CI checks pass.
• Check Storybook where applicable.
• Ensure there is a QA Brief.
• Ensure there are no unexpected significant changes to file sizes.

Merge Reviewer Checklist

• Ensure the PR has the correct target branch.
• Double-check that the PR is okay to be merged.
• Ensure the corresponding issue has a ZenHub release assigned.
• Add a changelog message to the issue.

[github-actions]

Build files for 9dee87e have been deleted.