Stop inserting redundant parenthesis around desugared match expressions

[robert-mccausland]

Currently the sugg utility treats all ExprKind::Match expressions as potentially needing brackets, and therefore many lints will add parenthesis around them. However this includes desugared match expressions like the ? and .await operators.

In this PR I have updated the utility to only treat match expressions which include a code block as needing parenthesis, as the other types have similar precedence rules and expectations to things like member access and I think can be treated like as such.

While this change is small on paper it touches a large amount of code due to changing a cross cutting concern, I am happy to add additional tests if we think it is needed, but I wanted to get a feel for if this is even a sensible change to be doing and what the expectations were around the level of testing needed before investing more time into it.

Regarding not putting a specific lint in the changelog, determining all the lints this could possibly effect would be possible but take some time, and I wonder if it would be a bit too noisy in the changelog. Open to suggestions about how best to address that.

fixes #16045

changelog: stop inserting unnecessary brackets around x? and x.await expressions in suggestions

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[github-actions]

Lintcheck changes for 466646f

Lint	Added	Removed	Changed
clippy::cast_sign_loss	0	0	2
clippy::if_then_some_else_none	0	0	1
clippy::option_if_let_else	0	0	7

This comment will be updated if you push new changes

[Alexendoo]

Looks great, thanks!

Yeah I think being general makes sense for the changelog

View changes since this review