Add more linters to improve code readability (#19989)

Add nakedret, unconvert, wastedassign, stylecheck and nolintlint linters to improve code readability

- nakedret - https://github.com/alexkohler/nakedret - nakedret is a Go static analysis tool to find naked returns in functions greater than a specified function length.
- unconvert - https://github.com/mdempsky/unconvert - Remove unnecessary type conversions
- wastedassign - https://github.com/sanposhiho/wastedassign -  wastedassign finds wasted assignment statements.
- notlintlint -  Reports ill-formed or insufficient nolint directives
- stylecheck - https://staticcheck.io/docs/checks/#ST - keep style consistent
  - excluded: [ST1003 - Poorly chosen identifier](https://staticcheck.io/docs/checks/#ST1003) and [ST1005 - Incorrectly formatted error string](https://staticcheck.io/docs/checks/#ST1005)

models/issues/tracked_time.go

@@ -63,7 +63,7 @@ func (t *TrackedTime) loadAttributes(ctx context.Context) (err error) {
 			return
 		}
 	}
-	return
+	return err
 }
 
 // LoadAttributes load Issue, User
@@ -73,7 +73,7 @@ func (tl TrackedTimeList) LoadAttributes() (err error) {
 			return err
 		}
 	}
-	return
+	return err
 }
 
 // FindTrackedTimesOptions represent the filters for tracked times. If an ID is 0 it will be ignored.
@@ -130,7 +130,7 @@ func (opts *FindTrackedTimesOptions) toSession(e db.Engine) db.Engine {
 // GetTrackedTimes returns all tracked times that fit to the given options.
 func GetTrackedTimes(ctx context.Context, options *FindTrackedTimesOptions) (trackedTimes TrackedTimeList, err error) {
 	err = options.toSession(db.GetEngine(ctx)).Find(&trackedTimes)
-	return
+	return trackedTimes, err
 }
 
 // CountTrackedTimes returns count of tracked times that fit to the given options.
@@ -291,7 +291,7 @@ func deleteTimes(ctx context.Context, opts FindTrackedTimesOptions) (removedTime
 	}
 
 	_, err = opts.toSession(db.GetEngine(ctx)).Table("tracked_time").Cols("deleted").Update(&TrackedTime{Deleted: true})
-	return
+	return removedTime, err
 }
 
 func deleteTime(ctx context.Context, t *TrackedTime) error {