Fix documentation inconsistencies

[kajes]

This fixes inconsistencies between the command help template and what is being generated as markdown.

Currently, the help template prints "Flags" and "Global Flags" when printing help for flags, while in the markdown, the two are printed as "Options" and "Options inherited from parent commands".

This Pull Request fixes this inconsistency, so that they both print the same. As for the actual formulation, I opted for using "Flags" and "Flags inherited from parent commands". In the latter case, I think this formulation actually represents it better than the previous "Global flags", since flags printed there are in fact inherited and not necessarily global in scope. This is, of course, up for discussion what to actually use.

Edit: Excuse the typo in the second commit message :grin:

[CLAassistant]

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