stream-clone: fix the help for an argument of perf::stream-locked-section

The help for `--stream-version` had a typo and missed a value.

contrib/perf.py

@@ -1964,7 +1964,7 b' def _find_stream_generator(version):'
             b'',
             b'stream-version',
             b'latest',
-            b'stream version to us ("v1", "v2" or "latest", (the default))',
+            b'stream version to use ("v1", "v2", "v3" or "latest", (the default))',
         ),
     ]
     + formatteropts,