MIR: improve dependency check section

[cpaelzer]

We had improved the related text in the general explanation in ed8ce6c,
but without being in the review section it might be forgotten too easily.

Discussing that in the MIR team meeting made it clear that we want an improvement of the related section.

To improve on this, we do:

• Extend the review section with related explanations in the RULE block
• Move the non useful tool check from TODO (kept) to rules (read but not kept in final comment)
• Refer to the now established section on rev-deps in the ubuntu project docs
• Make checking for runtime-deps and "stuff that kind of got into the binary" explicit separate aspects we check for.

[didrocks]

I like the change to move the tools themselves inside the RULES. I think the overall makes it clearer both in what to take into account and the why (especially the part about build-time dependencies ending up in the final binary).
Thanks for the change.

[joalif]

+1