perf-stream-locked-section: actually use v1 generation when requested

We were fetching a v1 generator but actually using the v2 function…

contrib/perf.py

@@ -2040,7 +2040,7 b' def _find_stream_generator(version):'
     if generatev1 is not None:
 
         def generate(repo):
-            entries, bytes, data = generatev2(repo, None, None, True)
+            entries, bytes, data = generatev1(repo, None, None, True)
             return data
 
         available[b'v1'] = generatev1