Allow repo admin to merge PR regardless of review status (#9611)

* Allow repo admin to merge even if review is not ok.

modules/auth/repo_form.go

@@ -448,6 +448,7 @@ type MergePullRequestForm struct {
 	Do                string `binding:"Required;In(merge,rebase,rebase-merge,squash)"`
 	MergeTitleField   string
 	MergeMessageField string
+	ForceMerge        *bool `json:"force_merge,omitempty"`
 }
 
 // Validate validates the fields