Add option to `makemigrations` to skip checking consistent history

[Curtis Maloney]

Whilst trying to set up a CI pipeline, I've run into the issue that makemigrations --cheeck still tries to connect to the database.

This is a problem because my CI pipeline doesn't have a DB to connect to.

I would like the option to cheaply check within my CI pipeline that there aren't any obviously forgotten migrations; and "cheaply" here means "without spending the time + bandwidth to stand up a DB service".

[David Sanders]

Normally feature requests have to go through the forum, but I tend to think we should accept this:

• I doubt the consistency check is useful in a CI context
• Setting up a DB in CI is not always an option if you have no control over CI
• It appears that skipping the consistency check is all that's required to get this to work (I did a basic test & confirmation)

Thoughts Sarah/Natalia/anyone else?

Edit: I guess the thing that would require discussing is: whether --check behaviour is updated or whether there'd be a new option… ?