For #255: Removes autoplay media feature flag

[sblatz]

Pull Request checklist

• Tests: This PR includes thorough tests or an explanation of why it does not
• Screenshots: This PR includes screenshots or GIFs of the changes made or an explanation of why it does not
• Accessibility: The code in this PR follows accessibility best practices or does not include any user facing features. In addition, it includes a screenshot of a successful accessibility scan to ensure no new defects are added to the product.

After merge

• Milestone: Make sure issues finished by this pull request are added to the milestone of the version currently in development.

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4. the APK links should be on the left side of the screen, named for each CPU architecture

[codecov-io]

Codecov Report

Merging #8198 into master will decrease coverage by 0.04%.
The diff coverage is 100%.

@@             Coverage Diff              @@
##             master    #8198      +/-   ##
============================================
- Coverage     18.76%   18.72%   -0.05%     
+ Complexity      454      452       -2     
============================================
  Files           315      315              
  Lines         12307    12300       -7     
  Branches       1617     1616       -1     
============================================
- Hits           2310     2303       -7     
- Misses         9797     9798       +1     
+ Partials        200      199       -1

Impacted Files	Coverage Δ	Complexity Δ
...pp/src/main/java/org/mozilla/fenix/FeatureFlags.kt	0% <ø> (-100%)	0 <0> (-2)
...ettings/sitepermissions/SitePermissionsFragment.kt	0% <ø> (ø)	0 <0> (ø)	⬇️
.../src/main/java/org/mozilla/fenix/utils/Settings.kt	71.86% <100%> (ø)	28 <0> (ø)	⬇️
app/src/main/java/org/mozilla/fenix/Config.kt	30.55% <0%> (-2.78%)	2% <0%> (ø)

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