Manually install zlib

.github/workflows/release.yml

@@ -64,6 +64,8 @@ jobs:
           brew install lhapdf
           # install APPLgrid's dependencies; disable ROOT because its static libraries are missing
           brew install --only-dependencies --without-hoppet --without-lhapdf --without-root applgrid
+          # install zlib, which is a dependency of APPLgrid but somehow missing
+          brew install zlib
           # APPLgrid wants to be linked against zlib, and we need to find its static library via pkg-config
           export PKG_CONFIG_PATH=$(find $(brew --cellar) -name '*.pc' -exec dirname {} + | sort -u | tr '\n' ':')
           # manually compile APPLgrid, because we need the file `appl_igrid.h` and the files it includes, which are possibly generated