fix(accessibility): frame must have a title attribute

[gjanblaszczyk]

Description

According to some HTML validators, the resize manager frame doesn't pass validation because the title attribute is not present.
Please check the below validators for details

1. https://rocketvalidator.com/accessibility-validation/frame-title-unique
2. https://equalizedigital.com/accessibility-checker/iframe-missing-title/

Specific Changes proposed

Add 'title' attribute.

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 #7754 (5afc7a1) into main (7e2b9ec) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #7754   +/-   ##
=======================================
  Coverage   80.91%   80.91%           
=======================================
  Files         116      116           
  Lines        7457     7457           
  Branches     1807     1807           
=======================================
  Hits         6034     6034           
  Misses       1423     1423           

Impacted Files	Coverage Δ
src/js/resize-manager.js	77.08% <ø> (ø)

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[gkatsev]

Validators are weird. Though, definitely no harm in having the title.

[mister-ben]

If it matters for accessibility it should probably be localised...

[gkatsev]

Given that the iframe should only be used on IE/older browsers (https://caniuse.com/resizeobserver), I'm not sure it's quite as necessary nowadays

[gjanblaszczyk]

@gkatsev Please, feel free to close this PR if you decide it is not needed nowadays.

Btw maybe it is a good time to remove a & Flash video player text from an About text. Rest in peace Flash player... I will never forget you :)

[misteroneill]

Good call! Updated the "About" section to remove the mention of Flash