[clang] [clang-format][NFC] Use `prog` in clang-format-diff.py (PR #74399)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang-format

Author: Owen Pan (owenca)

<details>
<summary>Changes</summary>

This is a minor improvement to #<!-- -->73491.

---
Full diff: https://github.com/llvm/llvm-project/pull/74399.diff


1 Files Affected:

- (modified) clang/tools/clang-format/clang-format-diff.py (+1-2) 


``````````diff
diff --git a/clang/tools/clang-format/clang-format-diff.py b/clang/tools/clang-format/clang-format-diff.py
index b25ee8f433751..946e28163420d 100755
--- a/clang/tools/clang-format/clang-format-diff.py
+++ b/clang/tools/clang-format/clang-format-diff.py
@@ -37,9 +37,8 @@
 
 
 def main():
-    basename = os.path.basename(sys.argv[0])
     parser = argparse.ArgumentParser(
-        description=__doc__.format(clang_format_diff=basename),
+        description=__doc__.format(clang_format_diff='%(prog)s'),
         formatter_class=argparse.RawDescriptionHelpFormatter,
     )
     parser.add_argument(

``````````

</details>


https://github.com/llvm/llvm-project/pull/74399