fix(progress): mouse-time-display overlaps the play-progress svg icon

[amtins]

Description

This PR fixes when the mouse hovers over the play-progress svg icon, the mouse-time-display bar appears above it.

Screencast.from.02.07.23.20.16.42.webm

Specific Changes proposed

• adds z-index to avoid overlap

Requirements Checklist

• Feature implemented / Bug fixed
• If necessary, more likely in a feature request than a bug fix
  • Change has been verified in an actual browser (Chrome, Firefox, IE)
  • Unit Tests updated or fixed
  • Docs/guides updated
  • Example created (starter template on JSBin)
• Reviewed by Two Core Contributors

[codecov]

Codecov Report

Merging #8338 (0b1c8eb) into main (2b0df25) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #8338   +/-   ##
=======================================
  Coverage   82.68%   82.68%           
=======================================
  Files         113      113           
  Lines        7561     7561           
  Branches     1818     1818           
=======================================
  Hits         6252     6252           
  Misses       1309     1309           

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