extend needless_borrowed_reference to lint mutable ref patterns

[Gri-ffin]

closes #16022

The lint should now also fire over &mut ref mut patterns when the matched reference can be moved instead of reborrowed. This is a bit conservative for now as it only handles cases where:

• the scrutinee is a simple local variable,
• the local is not used after the enclosing match/if let,
• and the pattern is not part of an or pattern or behind another reference pattern

There may be other valid cases but this should cover the straightforward ones without risking incorrect suggestions or complexities.

changelog: [needless_borrowed_reference] now also lints certain &mut ref mut patterns

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