style: gofumpt all the things (#9829)

Literally `gofumpt -w .` from the top level dir. Guaranteed to be minor
style changes only and nothing else.

@imsodin per request?

cmd/syncthing/debug.go

@@ -10,6 +10,4 @@ import (
 	"github.com/syncthing/syncthing/lib/logger"
 )
 
-var (
-	l = logger.DefaultLogger.NewFacility("main", "Main package")
-)
+var l = logger.DefaultLogger.NewFacility("main", "Main package")

cmd/syncthing/monitor_test.go

@@ -140,7 +140,7 @@ func checkNotExist(t *testing.T, name string) {
 func TestAutoClosedFile(t *testing.T) {
 	os.RemoveAll("_autoclose")
 	defer os.RemoveAll("_autoclose")
-	os.Mkdir("_autoclose", 0755)
+	os.Mkdir("_autoclose", 0o755)
 	file := filepath.FromSlash("_autoclose/tmp")
 	data := []byte("hello, world\n")