Commit 186e8db2 for libheif

commit 186e8db250508d47af0aabb12a0ef836ff7d48e5
Author: Dirk Farin <dirk.farin@gmail.com>
Date:   Mon Jun 1 00:46:02 2026 +0200

    add missing 'override' (#1832)

diff --git a/heifio/encoder_png.h b/heifio/encoder_png.h
index c03348d7..444cf3c1 100644
--- a/heifio/encoder_png.h
+++ b/heifio/encoder_png.h
@@ -67,7 +67,7 @@ public:
   bool supports_alpha() const override { return true; }

   void UpdateDecodingOptions(const heif_image_handle* handle,
-      heif_decoding_options* options) const;
+      heif_decoding_options* options) const override;

   bool Encode(const heif_image_handle* handle,
               const heif_image* image, const std::string& filename) override;