Fix Migration 136 (be less aggressive to open pulls missing git files) (#11072)

* be less aggressife to open pulls when migrating

* remove unused

models/migrations/v136.go

@@ -42,12 +42,6 @@ func addCommitDivergenceToPulls(x *xorm.Engine) error {
 		for _, pr := range results {
 			divergence, err := pull_service.GetDiverging(pr)
 			if err != nil {
-				if err = pr.LoadIssue(); err != nil {
-					return fmt.Errorf("pr.LoadIssue()[%d]: %v", pr.ID, err)
-				}
-				if !pr.Issue.IsClosed {
-					return fmt.Errorf("GetDiverging: %v", err)
-				}
 				log.Warn("Could not recalculate Divergence for pull: %d", pr.ID)
 				pr.CommitsAhead = 0
 				pr.CommitsBehind = 0