ref(api): Make processing team endpoints private

[loewenheim]

This makes the endpoints private that the processing team doesn't think should be public.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (61f933f) 81.39% compared to head (a286d2f) 81.25%.
Report is 646 commits behind head on master.

❗ Current head a286d2f differs from pull request most recent head 352d20f. Consider uploading reports for the commit 352d20f to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #63939      +/-   ##
==========================================
- Coverage   81.39%   81.25%   -0.15%     
==========================================
  Files        5228     5234       +6     
  Lines      232454   230518    -1936     
  Branches    40249    45234    +4985     
==========================================
- Hits       189217   187307    -1910     
+ Misses      37388    37371      -17     
+ Partials     5849     5840       -9     

Files	Coverage Δ
src/sentry/api/endpoints/chunk.py	87.95% <ø> (-0.15%)	⬇️
src/sentry/api/endpoints/debug_files.py	83.33% <ø> (-0.07%)	⬇️
...c/sentry/api/endpoints/event_apple_crash_report.py	57.69% <ø> (-1.57%)	⬇️
src/sentry/api/endpoints/event_reprocessable.py	82.60% <ø> (-0.73%)	⬇️
...endpoints/project_app_store_connect_credentials.py	44.84% <ø> (-0.29%)	⬇️
src/sentry/api/endpoints/project_reprocessing.py	85.71% <ø> (-0.96%)	⬇️

... and 2209 files with indirect coverage changes

[sentaur-athena]

I just replied in the channel and seems like from Dhrumil's comment we need to keep this one public.