refactor: small improvements and clean up (#3423)

* refactor: replace custom map functions with slice.Map

* refactor: extract StringerValue function

* refactor: removed unnecessary if

* chore: removed invalid comment

* refactor: replace more map functions

* chore: fix FFmpeg typo

log/log.go

@@ -7,7 +7,6 @@ import (
 	"io"
 	"net/http"
 	"os"
-	"reflect"
 	"runtime"
 	"sort"
 	"strings"
@@ -277,12 +276,7 @@ func addFields(logger *logrus.Entry, keyValuePairs []interface{}) *logrus.Entry
 				case time.Duration:
 					logger = logger.WithField(name, ShortDur(v))
 				case fmt.Stringer:
-					vOf := reflect.ValueOf(v)
-					if vOf.Kind() == reflect.Pointer && vOf.IsNil() {
-						logger = logger.WithField(name, "nil")
-					} else {
-						logger = logger.WithField(name, v.String())
-					}
+					logger = logger.WithField(name, StringerValue(v))
 				default:
 					logger = logger.WithField(name, v)
 				}