Auto merge of #18553 - mdboom:tidy-support-multiline-strings, r=wafflespeanut

Make tidy aware of Rust multiline strings

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This makes the internal tidy script properly ignore the contents of Rust multiline strings.

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #18551 (github issue number if applicable).

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- [X] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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components/script_plugins/unrooted_must_root.rs

@@ -163,7 +163,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for UnrootedPass {
     }
 }
 
-struct FnDefVisitor<'a, 'b: 'a, 'tcx: 'a+'b> {
+struct FnDefVisitor<'a, 'b: 'a, 'tcx: 'a + 'b> {
     cx: &'a LateContext<'b, 'tcx>,
     in_new_function: bool,
 }