Set the initial commit status to Success otherwise it will always be Pending (#10317) (#10318)

Backport #10317

The commit status code has a bug whereby setting the initial status to Pending means you can never have the status of Success - it should be set to Success.

services/pull/commit_status.go

@@ -23,7 +23,7 @@ func MergeRequiredContextsCommitStatus(commitStatuses []*models.CommitStatus, re
 		return structs.CommitStatusSuccess
 	}
 
-	var returnedStatus = structs.CommitStatusPending
+	var returnedStatus = structs.CommitStatusSuccess
 	for _, ctx := range requiredContexts {
 		var targetStatus structs.CommitStatusState
 		for _, commitStatus := range commitStatuses {