Merge pull request #1779 from ceph/dc-suite-fix

Fix scheduling regression

diff --cc teuthology/suite/run.py
index 239dc509fdd551dbf13f573685eb6984a35eacea,29f18ede36cd01e0a55eb54103c15d97d5197804..ab2d8f064f1b671239f84a5f731b625b54418a43
--- 1/teuthology/suite/run.py
--- 2/teuthology/suite/run.py
+++ b/teuthology/suite/run.py
@@@ -268,9 -264,16 +265,16 @@@ class Run(object)
                  f"file://{config.teuthology_path}",
                  teuthology_branch
              )
+         else:
+             if not teuthology_branch:
+                 teuthology_branch = 'main'
+             teuthology_sha1 = util.git_ls_remote(
+                 'teuthology',
+                 teuthology_branch
+             )
          if not teuthology_sha1:
              exc = BranchNotFoundError(teuthology_branch, build_git_url('teuthology'))
 -            util.schedule_fail(message=str(exc), name=self.name)
 +            util.schedule_fail(message=str(exc), name=self.name, dry_run=self.args.dry_run)
          log.info("teuthology branch: %s %s", teuthology_branch, teuthology_sha1)
          return teuthology_branch, teuthology_sha1