v8.15.0-rc2

Release 8.15.0-rc2

• Update dependencies to latest where possible.

Note

vips-dev-arm32-web-8.15.0-rc2-static.zip is not deployed due to rust-lang/backtrace-rs#572.

PDBs can be found here:
https://libvips-packaging.s3.amazonaws.com/pdb/index.html