contrib: flac: update to 1.4.0

This release brings many small improvements and a few large ones. Here are the most important for end-users:

FLAC can now encode and decode 32 bit-per-sample audio. This means the FLAC format is now one step closer to being fully implemented. Note that this is 32 bit integer samples, not 32 bit float samples. Compression for presets 3 through 8 has improved with only a small decrease in encoding speed, while presets 0, 1 and 2 got faster. Compression on 64-bit ARMv8 (used in for example new Apple computers) is now much faster

See: https://xiph.org/flac/2022/09/09/flac-1-4-0-released.html

Porting guide (I don't think any of the breaking changes apply for our modules): https://xiph.org/flac/api/group__porting__1__3__4__to__1__4__0.html