dev-cmd/unbottled: don't skip non-core formulae

[scpeters]

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Related to Homebrew/homebrew-test-bot#705, and I believe this doesn't conflict with #12325, which also modifies dev-cmd/unbottled. This allows the brew unbottled command to work for formulae in 3rd-party taps.

Before

$ brew unbottled osrf/simulation/gazebo9
==> Populating dependency tree...
==> :catalina bottle status
gazebo9: ready to bottle

After

$ brew unbottled osrf/simulation/gazebo9
==> Populating dependency tree...
==> :catalina bottle status
gazebo9: unbottled deps: ignition-cmake0 ignition-math4

[BrewTestBot]

Review period will end on 2021-11-19 at 16:29:46 UTC.

[MikeMcQuaid]

Thanks again @scpeters!

[BrewTestBot]

Review period skipped due to critical label.