Fix mock: use custom config with extra repos instead of --shell injection

The --init/--shell/--no-clean approach caused a corrupted RPM database
in the chroot. Instead, generate a custom mock config that includes
both the Forgejo package registry and the xlibre Copr repos directly
in config_opts['yum.conf'] before the chroot is created. This is the
standard, reliable way to add extra repositories to mock.

.forgejo/workflows/build-rpms.yml

@@ -50,18 +50,29 @@ jobs:
 
       - name: Build RPM with mock
         run: |
+          cat > /tmp/mock-custom.cfg <<'MOCKEOF'
+          include('/etc/mock/alma+epel-10-x86_64.cfg')
+          config_opts['yum.conf'] += """
+          [sonicde-rpm]
+          name=SonicDE RPM
+          baseurl=https://pc-rytteren.dk/forge/api/packages/anders/rpm
+          enabled=1
+          gpgcheck=0
+
+          [xlibre-xserver]
+          name=Copr xlibre-xserver
+          baseurl=https://download.copr.fedorainfracloud.org/results/@xlibre/xlibre-xserver/rhel+epel-10-$basearch/
+          type=rpm-md
+          skip_if_unavailable=True
+          gpgcheck=1
+          gpgkey=https://download.copr.fedorainfracloud.org/results/@xlibre/xlibre-xserver/pubkey.gpg
+          repo_gpgcheck=0
+          enabled=1
+          """
+          MOCKEOF
           mock \
-            --root alma+epel-10-x86_64 \
+            -r /tmp/mock-custom.cfg \
-            --init
-          FORGEJO_REPO=$(curl -fsSL https://pc-rytteren.dk/forge/api/packages/anders/rpm.repo)
-          COPR_REPO=$(curl -fsSL "https://copr.fedorainfracloud.org/coprs/g/xlibre/xlibre-xserver/repo/rhel+epel-10/group_xlibre-xlibre-xserver-rhel+epel-10.repo")
-          mock \
-            --root alma+epel-10-x86_64 \
-            --shell "mkdir -p /etc/yum.repos.d && echo '${FORGEJO_REPO}' > /etc/yum.repos.d/sonicde.repo && echo '${COPR_REPO}' > /etc/yum.repos.d/xlibre-xserver.repo"
-          mock \
-            --root alma+epel-10-x86_64 \
             --resultdir "${HOME}/mock-results" \
-            --no-clean \
             --rebuild "${{ env.SRPM_PATH }}"
 
       - name: Upload RPMs to Forgejo Package Registry