Reduce pytest prints (#117069)

* custom pytest-shard so I can control the verbosity (also index by 1 since it's confusing)
* normal runs (not keep-going) always rerun each failed test 9 times (3 per process, 3 processes).  Previously it would only run the entire test file 3 times, so if a test before you segfaulted, you only got 2 tries

Example of quieter log https://github.com/pytorch/pytorch/actions/runs/7481334046/job/20363147497
"items in shard" only gets printed once at the beginning, and the reruns just say how many got skipped.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/117069
Approved by: https://github.com/huydhn

pytest.ini

@@ -8,6 +8,8 @@ addopts =
     --capture=sys
     # don't suppress warnings, but don't shove them all to the end either
     -p no:warnings
+    # Use custom pytest shard located in test/pytest_shard_custom.py instead
+    -p no:pytest-shard
     # don't rewrite assertions (usually not a problem in CI due to differences in imports, see #95844)
     --assert=plain
 testpaths =