ref: fix some types for sentry.api

[asottile-sentry]

fixes errors when BaseManager becomes typed

[codecov]

Codecov Report

Attention: Patch coverage is 96.15385% with 2 lines in your changes missing coverage. Please review.

Project coverage is 78.06%. Comparing base (8d255a2) to head (4a7bf22).

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #72641   +/-   ##
=======================================
  Coverage   78.05%   78.06%           
=======================================
  Files        6597     6597           
  Lines      294016   294039   +23     
  Branches    50716    50716           
=======================================
+ Hits       229508   229533   +25     
- Misses      58246    58247    +1     
+ Partials     6262     6259    -3     

Files	Coverage Δ
src/sentry/api/endpoints/artifact_bundles.py	84.09% <100.00%> (ø)
src/sentry/api/endpoints/artifact_lookup.py	85.83% <100.00%> (ø)
src/sentry/api/endpoints/group_current_release.py	100.00% <100.00%> (ø)
.../endpoints/organization_artifactbundle_assemble.py	80.70% <100.00%> (ø)
.../endpoints/organization_codeowners_associations.py	100.00% <100.00%> (ø)
.../sentry/api/endpoints/organization_release_meta.py	85.36% <100.00%> (+4.11%)	⬆️
src/sentry/api/endpoints/prompts_activity.py	79.26% <100.00%> (ø)
src/sentry/api/helpers/teams.py	100.00% <100.00%> (ø)
src/sentry/api/serializers/models/filechange.py	100.00% <100.00%> (ø)
src/sentry/api/serializers/models/release.py	91.95% <100.00%> (+0.29%)	⬆️
... and 7 more

... and 6 files with indirect coverage changes