Code Formats, Nits & Unused Func/Var deletions (#15286)

* _ to unused func options

* rm useless brakets

* rm trifial non used models functions

* rm dead code

* rm dead global vars

* fix routers/api/v1/repo/issue.go

* dont overload import module

modules/markup/common/linkify.go

@@ -122,9 +122,7 @@ func (s *linkifyParser) Parse(parent ast.Node, block text.Reader, pc parser.Cont
 			}
 		}
 	}
-	if m == nil {
-		return nil
-	}
+
 	if consumes != 0 {
 		s := segment.WithStop(segment.Start + 1)
 		ast.MergeOrAppendTextSegment(parent, s)