Add Option for BashOperator to Set State to SKIPPED

[xyu]

Allow BashOperator Tasks to Skip instead of Fail

With the BashOperator sometimes I want to signal that the task should soft fail / return in a skipped state for itself and downstream tasks without having to hard fail it. I think it would be a good idea to add an option on the operator so that when the exit code matches what is given instead of failing task we raise a skip exception.

Related Issues

I've created #8244 as an example / idea of what I think could be done to implement this feature.

[boring-cyborg]

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[ashb]

Closed by #13421 but exit code will be changed in #14963