Fix mypy

[sentrivana]

mypy is unhappy in CI, fix it.

[codecov]

Codecov Report

Attention: Patch coverage is 90.00000% with 1 line in your changes missing coverage. Please review.

Project coverage is 80.23%. Comparing base (797e82f) to head (2bc46ae).
Report is 1 commits behind head on master.

✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
sentry_sdk/integrations/tornado.py	0.00%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #4019   +/-   ##
=======================================
  Coverage   80.22%   80.23%           
=======================================
  Files         139      139           
  Lines       15399    15403    +4     
  Branches     2601     2601           
=======================================
+ Hits        12354    12358    +4     
  Misses       2203     2203           
  Partials      842      842           

Files with missing lines	Coverage Δ
sentry_sdk/integrations/grpc/__init__.py	91.89% <100.00%> (ø)
sentry_sdk/integrations/socket.py	94.00% <100.00%> (+0.52%)	⬆️
sentry_sdk/integrations/tornado.py	80.53% <0.00%> (ø)