Descriptive item properties are after transformative item properties in some test files

[wantehchang]

Descriptive item properties are after transformative item properties in the following test files:

• Link-U/kimono.mirror-horizontal.avif
• Link-U/kimono.mirror-vertical.avif
• Link-U/kimono.mirror-vertical.rotate270.avif
• Link-U/kimono.mirror-vertical.rotate270.crop.avif
• Link-U/kimono.rotate270.avif
• Link-U/kimono.rotate90.avif

It is better to list descriptive item properties before transformative item properties because ISO/IEC 23008-12:2022 (HEIF) Clause 6.5.1 has the following requirement:

Readers shall allow and ignore descriptive properties following the first transformative or unrecognized property, whichever is earlier, in the sequence associating properties with an item.

Although this problematic requirement will be removed in Amd2 of HEIF (see MPEGGroup/FileFormat#113), these test files don't need to violate this requirement.