For #6992, for #6897, for #6889: Disable multitouch in app

[mcarare]

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Pull Request checklist

• Quality: This PR builds and passes detekt/ktlint checks (A pre-push hook is recommended)
• 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

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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[mcarare]

IMO the only place Fenix needs multitouch is in browser window. This change does not affect zooming or multiple touches inside engineView, because it prevents multiple touches in a ViewGroupnot in a single View.
Also , I tested zoom and multitouch inside browser window and they still work.

[codecov-io]

Codecov Report

Merging #6999 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##             master   #6999   +/-   ##
========================================
  Coverage      18.6%   18.6%           
  Complexity      413     413           
========================================
  Files           282     282           
  Lines         11165   11165           
  Branches       1524    1524           
========================================
  Hits           2077    2077           
  Misses         8926    8926           
  Partials        162     162

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[sblatz]

Looks good 😄