[exportdb] Change case ids to case names for UserErrors. (#100600)
Associate UserErrors with the unique case name instead of the
case ids, because in practice they work similarly but names are more
meaningful to use and remember.
Fixes #ISSUE_NUMBER
Pull Request resolved: https://github.com/pytorch/pytorch/pull/100600
Approved by: https://github.com/angelayi, https://github.com/avikchaudhuri
