Add license-expression Python package to builders

It'll be useful for combining the SPDX expressions of the dependencies.

Signed-off-by: Benjamin Gilbert <bgilbert@cs.cmu.edu>

Author: bgilbert

.github/workflows/build.yml

@@ -185,8 +185,9 @@ jobs:
           done
           brew update
           brew install meson
-          # needed by glib
-          python3 -m pip install --break-system-packages packaging
+          # packaging needed by glib
+          python3 -m pip install --break-system-packages license-expression \
+              packaging
       - name: Download source tarball
         uses: actions/download-artifact@v4
         with:

builder/linux/Dockerfile

@@ -3,11 +3,11 @@ FROM quay.io/almalinuxorg/almalinux:8
 # NOTE: try to keep the current container image compatible with the latest
 # stable source release, so people can conveniently build from the source
 # tarball
-RUN touch /etc/openslide-linux-builder-v5
+RUN touch /etc/openslide-linux-builder-v{5,6}
 RUN dnf -y upgrade && \
     dnf -y install 'dnf-command(config-manager)' epel-release && \
     dnf config-manager --set-enabled powertools && \
     dnf -y install gcc-c++ git-core nasm ninja-build patchelf \
     python3.12-pip && \
     dnf clean all
-RUN pip3 install auditwheel meson
+RUN pip3 install auditwheel license-expression meson

builder/windows/Dockerfile

@@ -2,7 +2,7 @@ FROM docker.io/gentoo/stage3:latest
 # NOTE: try to keep the current container image compatible with the latest
 # stable source release, so people can conveniently build from the source
 # tarball
-RUN touch /etc/openslide-winbuild-builder-v6
+RUN touch /etc/openslide-winbuild-builder-v{6,7}
 RUN echo 'FEATURES="-sandbox -usersandbox -ipc-sandbox -network-sandbox -pid-sandbox"' >> /etc/portage/make.conf
 COPY package.accept_keywords /etc/portage/package.accept_keywords/openslide
 COPY package.use /etc/portage/package.use/openslide
@@ -12,7 +12,8 @@ COPY --from=docker.io/gentoo/portage:latest /var/db/repos/gentoo /var/db/repos/g
 RUN emerge -u dev-build/meson && \
     rm -f /var/cache/distfiles/*
 RUN emerge app-portage/gentoolkit dev-lang/nasm dev-libs/glib \
-    dev-util/glib-utils dev-vcs/git sys-devel/crossdev && \
+    dev-python/license-expression dev-util/glib-utils dev-vcs/git \
+    sys-devel/crossdev && \
     rm /var/cache/distfiles/*
 RUN crossdev -t x86_64-w64-mingw32 && \
     rm /var/cache/distfiles/*