cmd/bump: add --installed flag

[apainintheneck]

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Closes #15803.

This allows users to only try to bump formulae and casks they currently have installed. It copies this behavior from the livecheck command.

@osalbahr Is this what you had in mind here?

[osalbahr]

I’m not at my laptop to test rn, but yeah as long as it makes brew bump run on installed formulate/casks yeah this is exactly it. Thx!

[MikeMcQuaid]

Thanks again @apainintheneck!