Avoid too many Blank Lines

[christianbraeunlich]

I'd like to avoid too many blank lines.

Inspired by:

• https://www.python.org/dev/peps/pep-0008/#blank-lines
• https://www.flake8rules.com/rules/E303.html

[fvet]

Not a rule, but definitely interesting if this could be part of the 'Code Cleanup' actions.
anzwdev/al-code-outline#347

[christianbraeunlich]

If there is an action for it, then there is a rule for it. The action is based on this rule...or is a rule based on an action? If for some reason you don't apply the action, you run the risk of committing those unnecessary blank lines. A centralized pipeline ensures that this rule is reviewed.