Rules.Idomatic: update switch for new macro enumerator

[compnerd]

The introduction of the macro enumerator in the enumeration causes a build break due to an uncovered switch. Conservatively treat the macros as being exempt from the ACLing.

[SwiftLintBot]

	1 Error
🚫	Could not build branch

	1 Warning
⚠️	If this is a user-facing change, please include a CHANGELOG entry to credit yourself! You can find it at CHANGELOG.md.

Here's an example of your CHANGELOG entry:

* Rules.Idomatic: update switch for new `macro` enumerator.  
  [compnerd](https://github.com/compnerd)
  [#issue_number](https://github.com/realm/SwiftLint/issues/issue_number)

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[SimplyDanny]

I think this is no longer required with the SwiftSyntax rewrite in #5382.

Thank you nevertheless, @compnerd!

[compnerd]

@SimplyDanny sounds good! BTW, I wouldn't mind some early feedback on #5030 (I'm happy to split that into separate PRs, but want to gauge the interest and any easy things that can be addressed up front).