If you're reading about this commit from an autogenerated changelog entry, this should have no user-visible impact on how the stubs are interpreted by a type checker; it's just an internal change to how typeshed's tests work.
I spent far too much time being confused about why pyanalyze thought `pymysql.converters.escape_dict` only takes two arguments.
I rewrote the stubs from scratch using the implementation: https://github.com/PyMySQL/PyMySQL/blob/main/pymysql/converters.py.
The "charset" argument is ignored as far as I can tell; it gets passed to other functions but no function actually uses it.
Co-authored-by: Sebastian Rittau <srittau@rittau.biz>
