shard `linux-xenial-py3.7-clang7-asan / test (default` from 4 to 5 (#77084)
Notes
- still over 2 hrs even with 4 shards so try 5 shards
- i think 6 shards was a bit unbalanced, will need to test some other time
sharding spreadsheet: https://docs.google.com/spreadsheets/d/1BdtVsjRr0Is9LXMNilR02FEdPXNq7zEWl8AmR3ArsLQ/edit#gid=1242752407
Pull Request resolved: https://github.com/pytorch/pytorch/pull/77084
Approved by: https://github.com/janeyx99
