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/queue/queue_redis.go

@@ -69,7 +69,7 @@ type redisClient interface {
 	Close() error
 }
 
-var _ (ByteFIFO) = &RedisByteFIFO{}
+var _ ByteFIFO = &RedisByteFIFO{}
 
 // RedisByteFIFO represents a ByteFIFO formed from a redisClient
 type RedisByteFIFO struct {