make black formatting consistent on desktop and in CI

[gvwilson]

We discovered while working on #5199 that black behaves differently when run during codegen than when run directly on the command line (as it is in CI). We suspect this may be because codegen runs black separately for three sub-directories, while black --check . --exclude .venv (as used in CI) runs it from the root directory. These need to be reconciled.