Update to Muon 4.7.6

[bsclifton]

Auditors: @bbondy, @bridiver

Fixes #12824

Submitter Checklist:

• Submitted a ticket for my issue if one did not already exist.
• Used Github auto-closing keywords in the commit message.
• Added/updated tests for this change (for new code or code which already has tests).
• Ran git rebase -i to squash commits (if needed).
• Tagged reviewers and labelled the pull request as needed.
• Request a security/privacy review as needed. (Ask a Brave employee to help if you cannot access this document.)

Test Plan:

Reviewer Checklist:

• Request a security/privacy review as needed if one was not already requested.

Tests

• Adequate test coverage exists to prevent regressions
• Tests should be independent and work correctly when run individually or as a suite ref
• New files have MPL2 license header

[bsclifton]

Cherry-picked to 0.19.x with 098eb60

[codecov-io]

Codecov Report

Merging #12847 into master will decrease coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #12847      +/-   ##
==========================================
- Coverage   56.13%    56.1%   -0.04%     
==========================================
  Files         279      279              
  Lines       27319    27319              
  Branches     4443     4443              
==========================================
- Hits        15336    15327       -9     
- Misses      11983    11992       +9

Flag	Coverage Δ
#unittest	56.1% <ø> (-0.04%)	⬇️

Impacted Files	Coverage Δ
js/stores/appStoreRenderer.js	91.17% <0%> (-8.83%)	⬇️
app/renderer/components/reduxComponent.js	84.61% <0%> (-6.16%)	⬇️
js/stores/windowStore.js	27.25% <0%> (-0.31%)	⬇️

[bridiver]

++

[bsclifton]

master f4d07bd
0.21.x 62bae11
0.20.x ae21989
0.19.x 098eb60