Don't sync read-only file handle

internal/filewatcher/watch.go

@@ -157,29 +157,20 @@ func hasGoFiles(path string) bool {
 	if err != nil {
 		return false
 	}
-	defer fh.Close()
+	defer fh.Close() // nolint: errcheck // fh is opened read-only
 
 	for {
 		names, err := fh.Readdirnames(20)
 		switch {
 		case err == io.EOF:
-			if err := fh.Sync(); err != nil {
-				panic(err)
-			}
 			return false
 		case err != nil:
 			log.Warnf("failed to read directory %v: %v", path, err)
-			if err := fh.Sync(); err != nil {
-				panic(err)
-			}
 			return false
 		}
 
 		for _, name := range names {
 			if strings.HasSuffix(name, ".go") {
-				if err := fh.Sync(); err != nil {
-					panic(err)
-				}
 				return true
 			}
 		}