This guarantees $(package)_sha256_hash reproducibility regardless of the default behavior of $(build_TAR).
Fixes caching on some systems, for example, on FreeBSD, on OpenBSD or on macOS.
Steps to reproduce the issue on FreeBSD using the master branch @ 2a9e35d293b308e81811fa93ad2e5e8ed20e66e0:
$ pkg update
$ pkg install -y bash git gmake
$ mkdir a && cd a && git init
$ git remote add origin https://github.com/bitcoin/bitcoin.git
$ git fetch --depth 1 origin 2a9e35d293b308e81811fa93ad2e5e8ed20e66e0
$ git checkout FETCH_HEAD
$ cd depends
$ gmake print-native_libmultiprocess_sha256_hash
native_libmultiprocess_sha256_hash=7dd817bfc0ee23c408299907aff13fefb0bd3a54ec66dc14ea15b0cc38c3d9ce
$ cd ../../ && sleep 2
$ mkdir b && cd b && git init
$ git remote add origin https://github.com/bitcoin/bitcoin.git
$ git fetch --depth 1 origin 2a9e35d293b308e81811fa93ad2e5e8ed20e66e0
$ git checkout FETCH_HEAD
$ cd depends
$ gmake print-native_libmultiprocess_sha256_hash
native_libmultiprocess_sha256_hash=34d6f79560c0ff7a4f46bd6bfb4693076546b41f071b6dbf879da45ac8384688
The CI run for this branch: https://github.com/hebasto/github-actions/actions/runs/28376051724/job/84065853378.
