Should the destructor of decoder_context include more cleanups?

[farindk]

Copied from: strukturag/libheif#1166 (comment)

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Inside the reset method of the decoder_context the following is done:

  dpb.clear();

  nal_parser.remove_pending_input_data();

Should this not also be done inside the destructor of decoder_context? We are getting an oss-fuzz error report about memory leaks of NAL_unit in the oss-fuzz tooling of @ImageMagick and it looks like it is happening because of this?