Bump dep: heif

Upgrade to libvips v8.16.0-rc2 (#255)

* cargo-c: ensure deterministic build

Upgrade to libvips v8.16.0-rc1 (#253)

Add libvips version number to shared library SONAME and filename (#252)

This should help improve support for multiple versions of sharp
that use differing versions of libvips running within the same
process by ensuring dlopen accesses the relevant shared library.

Upgrade to libvips v8.15.3 (#245)

rsvg: pin to version 2.57.2

aom: new musl-only patch to set min thread stack size

The aom dependency implemented a minimum stack size for
debugging purposes in v3.8.0. This patch enables it for
production use, reducing the minimum from 1MB to 256 KB.

The previous patch was temporarily removed in de30aa6.

Upgrade to libvips v8.15.0

Upgrade to libvips v8.15.0-rc2 (#203)

Leave tarballs as-is, remove Brotli, don't re-gzip (#199)

These files will no longer be downloaded millions of times,
so there is no need to spend CPU time maximising compression.