For #11642: disables crashing UI test privateModeScreenItemsTest

[sv-ohorvath]

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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2. click Details next to "Taskcluster (pull_request)" after it appears and then finishes with a green checkmark,
3. click on the "Fenix - assemble" task, then click "Run Artifacts".
4. the APK links should be on the left side of the screen, named for each CPU architecture

[codecov-commenter]

Codecov Report

Merging #11768 into master will increase coverage by 0.00%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master   #11768   +/-   ##
=========================================
  Coverage     21.92%   21.92%           
  Complexity      716      716           
=========================================
  Files           376      376           
  Lines         15054    15055    +1     
  Branches       1954     1954           
=========================================
+ Hits           3300     3301    +1     
  Misses        11472    11472           
  Partials        282      282           

Impacted Files	Coverage Δ	Complexity Δ
...ug/java/org/mozilla/fenix/DebugFenixApplication.kt	0.00% <0.00%> (ø)	0.00% <0.00%> (ø%)
app/src/main/java/org/mozilla/fenix/Config.kt	36.11% <0.00%> (+2.77%)	2.00% <0.00%> (ø%)

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