deps command: add --include-implicit flag

[Moisan]

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same change?
• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes? Here's an example.
• Have you successfully run brew style with your changes locally?
• Have you successfully run brew typecheck with your changes locally?
• Have you successfully run brew tests with your changes locally?

---

This is a follow-up of Homebrew/homebrew-core#201901: it adds the --include-implicit flag to brew deps and brew uses.

Once this is merged we can update the scheduled.yml workflow on homebrew-core to use this command instead of the current ruby one-liner.

[MikeMcQuaid]

Thanks! Still needs some work. What is an implicit dependency?

[MikeMcQuaid]

This seems to be wrong?

[Moisan]

Oops, I think I copy-pasted from somewhere else and forgot to update the description.

[Moisan]

What is an implicit dependency?

I took the definition of implicit dependency from formula.rb

They are also used in a lot in dependency_collector.rb.