Replace binfmt container with Debian qemu-user-static.

Sporatic crashes with qemu for arm64 started to occur after kernel
hardenning changes on GitHub runners. Crashes are caused by qemu being compiled
with `--disable-pie`. The setup-qemu-action@v3 action uses qemu v7 from
tonistiigi/binfmt:latest (compiled with this option). Using
tonistiigi/binfmt:v8.1.5 (compiled without the option) has been suggested to fix
this issue, but crashes are still seen (probably related to the v8
itself). Unfortunately, tonistiigi/binfmt is not providing v7 being
compiled without the option yet.

In the meantime, install binfmt manually from Debian package.

.github/workflows/build-baseimage.yml

@@ -128,9 +128,15 @@ jobs:
         uses: mig4/setup-bats@v1
 
       - name: Setup QEMU
-        uses: docker/setup-qemu-action@v3
-        with:
-          platforms: arm,arm64,ppc64le,mips64,s390x
+        #uses: docker/setup-qemu-action@v3
+        #with:
+        #  platforms: arm,arm64,ppc64le,mips64,s390x
+        shell: bash
+        run: |
+          # Temporarily use Debian qemu-user-static, until Ubuntu fixes theirs.
+          wget -q http://ftp.debian.org/debian/pool/main/q/qemu/qemu-user-static_7.2+dfsg-7+deb12u12_amd64.deb
+          echo "1a2696081c1f30d464f79fd300196822397c77f05440ea9ce6dc8e9658b595ec qemu-user-static_7.2+dfsg-7+deb12u12_amd64.deb" | sha256sum -c
+          sudo dpkg -i qemu-user-static_7.2+dfsg-7+deb12u12_amd64.deb
 
       - name: Setup Docker Buildx
         uses: docker/setup-buildx-action@v3