[GHF] Add checkruns pagination (#77922)
Rename `GH_GET_PR_NEXT_CHECK_RUNS` into `GH_GET_PR_NEXT_CHECKSUITES`
(because this is what it does)
Modify `checkSuites` checkout loop to query edges and request cursor for
every nodes
Add `GH_GET_PR_NEXT_CHECK_RUNS` which takes two cursors - one to
checkSuite and another for checkrun
Added `test_get_checkruns_many_runs` test and verified that it works by looking for `cr_cursor` ins `gql_mocks.json`
Pull Request resolved: https://github.com/pytorch/pytorch/pull/77922
Approved by: https://github.com/suo, https://github.com/seemethere
