More strict format checking on white spaces

[BenjaminRodenberg]

When merging 2d36127 I realized that there are some white space changes that are somehow not taken care of by our formatter. This ambiguity always leads to a lot of manual work and I would rather have one clear rule here that is enforced by the formatter.

@IshaanDesai I have the impression that we have different VSCode settings and this might cause the white space inconsistency. Do you also observe this from time to time? Maybe in other repositories like the fenics-adapter, as well?