Fix "FirebaseFirestore has already been started" sync failures

[gino-m]

Uses same singleton provider to get Firebase instance when generating UUIDs as used elsewhere. This requires those calls to be made asynchronously to avoid blocking the UI.

Fixes #2377

[codecov]

Codecov Report

Attention: Patch coverage is 76.92308% with 6 lines in your changes missing coverage. Please review.

Project coverage is 61.32%. Comparing base (17790f3) to head (2514fb0).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
...ui/datacollection/tasks/photo/PhotoTaskFragment.kt	0.00%	5 Missing ⚠️
...i/datacollection/tasks/photo/PhotoTaskViewModel.kt	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #2834      +/-   ##
============================================
- Coverage     61.35%   61.32%   -0.04%     
  Complexity     1169     1169              
============================================
  Files           266      266              
  Lines          6306     6316      +10     
  Branches        900      900              
============================================
+ Hits           3869     3873       +4     
- Misses         1909     1915       +6     
  Partials        528      528              

Files with missing lines	Coverage Δ
...tence/remote/firebase/FirebaseFirestoreProvider.kt	0.00% <ø> (ø)
...e/android/ground/repository/UserMediaRepository.kt	71.42% <100.00%> (+1.05%)	⬆️
...round/ui/datacollection/DataCollectionViewModel.kt	71.57% <100.00%> (ø)
...datacollection/tasks/point/DropPinTaskViewModel.kt	93.93% <100.00%> (+0.39%)	⬆️
...acollection/tasks/polygon/DrawAreaTaskViewModel.kt	89.18% <100.00%> (+0.14%)	⬆️
...i/datacollection/tasks/photo/PhotoTaskViewModel.kt	22.50% <0.00%> (-0.58%)	⬇️
...ui/datacollection/tasks/photo/PhotoTaskFragment.kt	32.53% <0.00%> (-1.22%)	⬇️

... and 1 file with indirect coverage changes