Close #10543. Add If-Unused and If-Empty support for delete_queue for QQs

[ikavgo]

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Further Comments

Couldn't find any test suite for this. Tested manually.

[michaelklishin]

We should have some tests for these two (three, four) new combinations of queue.delete parameters.

[ikavgo]

Agree, did I miss existing tests though?

[michaelklishin]

@ikavgo there are these two that test deletion of QQs https://github.com/rabbitmq/rabbitmq-server/blob/main/deps/rabbit/test/quorum_queue_SUITE.erl#L74-L75

[kjnilsson]

There is no need to line up bits of code like that. Please only use a single white space between things.
If you want the start of clauses to line up in columns use newlines.