Remove unused SubstitutionCorrectableASTRule protocol

[jpsim]

Last use was removed in #4192.

[SwiftLintBot]

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

	17 Messages
📖	Linting Aerial with this PR took 1.18s vs 1.19s on main (0% faster)
📖	Linting Alamofire with this PR took 1.56s vs 1.56s on main (0% slower)
📖	Linting Brave with this PR took 8.87s vs 8.9s on main (0% faster)
📖	Linting DuckDuckGo with this PR took 4.45s vs 4.46s on main (0% faster)
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📖	Linting Moya with this PR took 0.62s vs 0.63s on main (1% faster)
📖	Linting NetNewsWire with this PR took 3.26s vs 3.27s on main (0% faster)
📖	Linting Nimble with this PR took 0.82s vs 0.82s on main (0% slower)
📖	Linting PocketCasts with this PR took 8.7s vs 8.72s on main (0% faster)
📖	Linting Quick with this PR took 0.4s vs 0.4s on main (0% slower)
📖	Linting Realm with this PR took 11.67s vs 11.69s on main (0% faster)
📖	Linting Sourcery with this PR took 2.8s vs 2.81s on main (0% faster)
📖	Linting Swift with this PR took 5.23s vs 5.22s on main (0% slower)
📖	Linting VLC with this PR took 1.54s vs 1.55s on main (0% faster)
📖	Linting Wire with this PR took 19.46s vs 19.49s on main (0% faster)
📖	Linting WordPress with this PR took 13.14s vs 13.17s on main (0% faster)

Here's an example of your CHANGELOG entry:

* Remove unused `SubstitutionCorrectableASTRule` protocol.  
  [jpsim](https://github.com/jpsim)
  [#issue_number](https://github.com/realm/SwiftLint/issues/issue_number)

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