[llvm][utils] Correct misleading comment in bump-version.py

It's using packaging not distutils.

Relates to #54337 (comment)

Author: DavidSpickett

llvm/utils/release/bump-version.py

@@ -169,7 +169,7 @@ def process_line(self, line: str) -> str:
 
     verstr = args.version
 
-    # parse the version string with distutils.
+    # parse the version string.
     # note that -rc will end up as version.pre here
     # since it's a prerelease
     version = packaging.version.parse(verstr)