Fix remaining wsl_v5 whitespace findings (refs #61)

Insert the blank line wsl_v5 requires above `defer` and `go`
statements that share no variables with the statement above them.
Applied mechanically via `make lint-fix`; the diff is 60 added blank
lines and nothing else.

internal/storage/file.go

@@ -62,6 +62,7 @@ func (f *FileStorer) Put(_ context.Context, key string, data io.Reader) error {
 	if err != nil {
 		return fmt.Errorf("creating file: %w", err)
 	}
+
 	defer func() { _ = file.Close() }()
 
 	_, err = io.Copy(file, data)
@@ -91,6 +92,7 @@ func (f *FileStorer) PutWithProgress(
 	if err != nil {
 		return fmt.Errorf("creating file: %w", err)
 	}
+
 	defer func() { _ = file.Close() }()
 
 	// Wrap with progress tracking
@@ -209,6 +211,7 @@ func (f *FileStorer) List(ctx context.Context, prefix string) ([]string, error)
 // ListStream returns a channel of ObjectInfo for large result sets.
 func (f *FileStorer) ListStream(ctx context.Context, prefix string) <-chan ObjectInfo {
 	ch := make(chan ObjectInfo)
+
 	go func() {
 		defer close(ch)