Remove unused function in download package

internal/download/Download.go

@@ -237,22 +237,3 @@ func downloadFile(url, destPath string, onChunk func(int64)) (int64, error) {
 
 	return total, nil
 }
-
-// ensureDir creates path and all parents if they don't exist.
-func ensureDir(path string) error {
-	info, err := os.Stat(path)
-	if err == nil {
-		if !info.IsDir() {
-			return fmt.Errorf("path exists but is not a directory: %s", path)
-		}
-		return nil
-	}
-	if !os.IsNotExist(err) {
-		return fmt.Errorf("stat %s: %w", path, err)
-	}
-	if err := os.MkdirAll(path, 0o750); err != nil {
-		return fmt.Errorf("mkdir %s: %w", path, err)
-	}
-	logger.Info("download: created directory %s", path)
-	return nil
-}