ci: enable mgr suite for PR only
ci: enable mgr suite for PR only

this commit enable mgr suite to run only
for PRs.

Signed-off-by: subhamkrai <bb6131f7fb4bb2a9ce18c6dfefd4c517b6b3ce6a@redhat.com>

rook/rook,rook/nfs,rook/rook,rook/nfs,rook/rook,rook/nfs,rook/rook,rook/rook