[clang] [clang][Python] Use fstrings instead of string concatenations (PR #173861)

[Vlad Serebrennikov via cfe-commits]

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@@ -3604,7 +3589,7 @@ def reparse(self, unsaved_files=None, options=0):
             )
         )
         if result != 0:
-            msg = "Error reparsing translation unit. Error code: " + str(result)
+            msg: str = f"Error reparsing translation unit. Error code: {result}"
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Endilll wrote:

Adding a type annotation doesn't fit the scope of the PR as declared by the title. Let's leave it for another day.

https://github.com/llvm/llvm-project/pull/173861