mypy

e0567745 - Restrict the number of errors shown when there are missing stubs (#10579)

Restrict the number of errors shown when there are missing stubs (#10579) When upgrading to mypy 0.900, most projects will see some errors about missing stubs. Projects with strict settings could see thousands of errors, since missing stubs will generate many additional Any types. After 200 errors (only if some of them are about imports) we will now only show errors about unresolved imports or missing stubs, so that the likely root causes won't be obscured in a high volume of errors. Fixes #10529.