Fix/11134
Fix#11134
Hir of `qpath` will be `TypeRelative(Ty { kind: Path(LangItem...` when a closure contains macro (e.g. https://github.com/rust-lang/rust-clippy/issues/11651) and #11134, it causes panic.
This PR avoids panicking and emitting incomplete path string when `qpath` contains `LangItem`.
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