For #10036 - Workaround for System Theme changes with config change

[ekager]

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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[codecov-io]

Codecov Report

Merging #10074 into master will increase coverage by 0.00%.
The diff coverage is 0.00%.

@@            Coverage Diff            @@
##             master   #10074   +/-   ##
=========================================
  Coverage     19.26%   19.27%           
  Complexity      532      532           
=========================================
  Files           340      340           
  Lines         13790    13792    +2     
  Branches       1847     1847           
=========================================
+ Hits           2657     2658    +1     
- Misses        10895    10896    +1     
  Partials        238      238           

Impacted Files	Coverage Δ	Complexity Δ
...rc/main/java/org/mozilla/fenix/FenixApplication.kt	12.24% <0.00%> (-0.17%)	4.00 <0.00> (ø)
...ix/home/sessioncontrol/SessionControlController.kt	72.72% <0.00%> (+0.90%)	0.00% <0.00%> (ø%)

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[ekager]

I tested this and locales still switch immediately. 👍

[mcarare]

LGTM!