Flake8 linter fixes + updating PR lint rules

[teoparvanov]

Here we update the ubuntu.yml workflow to use the same (OpenFL-specific) lint rules as the lint.yml workflow that runs as part of the PR pipeline.

[MasterSkepticista]

@teoparvanov Those do not appear in Lint CI because there are exceptions to flake8 provided via a config file in shell/lint.sh, and it only covers source code, no examples/tutorials/templates.

I think we need to remove all flake8 checks elsewhere. Any exceptions should be captured in setup.cfg.

[teoparvanov]

@teoparvanov Those do not appear in Lint CI because there are exceptions to flake8 provided via a config file in shell/lint.sh, and it only covers source code, no examples/tutorials/templates.

I think we need to remove all flake8 checks elsewhere. Any exceptions should be captured in setup.cfg.

Thanks for pointing this out, @MasterSkepticista , I wasn't aware of the setup.cfg file. Let me take a look and I'll update the PR accordingly.

[MasterSkepticista]

JFYI: For files in openfl-workspace, this formatting was done to silence previous flake8 errors, but it won't make any difference in the future since ./shell/lint.sh only covers openfl/** code.

You may choose to keep these changes or only keep ubuntu.yml and lint.yml changes.