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?

lib/versioner/trashcan_test.go

@@ -182,7 +182,7 @@ func readFile(t *testing.T, filesystem fs.Filesystem, name string) string {
 }
 
 func writeFile(t *testing.T, filesystem fs.Filesystem, name, content string) {
-	fd, err := filesystem.OpenFile(name, fs.OptReadWrite|fs.OptCreate, 0777)
+	fd, err := filesystem.OpenFile(name, fs.OptReadWrite|fs.OptCreate, 0o777)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -213,7 +213,7 @@ func TestTrashcanCleanOut(t *testing.T) {
 
 	v := newTrashcan(cfg)
 
-	var testcases = map[string]bool{
+	testcases := map[string]bool{
 		".stversions/file1":                     false,
 		".stversions/file2":                     true,
 		".stversions/keep1/file1":               false,
@@ -229,7 +229,7 @@ func TestTrashcanCleanOut(t *testing.T) {
 	t.Run("trashcan versioner trashcan clean up", func(t *testing.T) {
 		oldTime := time.Now().Add(-8 * 24 * time.Hour)
 		for file, shouldRemove := range testcases {
-			fs.MkdirAll(filepath.Dir(file), 0777)
+			fs.MkdirAll(filepath.Dir(file), 0o777)
 
 			writeFile(t, fs, file, "some content")