[rfc] Delete devtools_check_repro workflow

With GitHub issue templates this workflow is not truly necessary and
can deny other workflows from running due to a limited amount of CI
workers in the pool.

I propose deleting this workflow and relying on issue templates instead.

ghstack-source-id: a798621f3625fa8fffaade5a987e4024553aefa0
Pull Request resolved: https://github.com/facebook/react/pull/30518