CI: use our buildiso with --overwrite='*' to resolve calamares branding file conflict

- Stock buildiso from artools passes --overwrite='*' through basestrap
  to pacman (basestrap stuffs all remaining args into pacman_args).
  Our copy already has this flag; CI was ignoring it.
- Add jack2, noto-fonts-emoji to common.yaml to pre-resolve provider
  prompts before they block the build.

.github/workflows/build.yml

@@ -49,7 +49,7 @@ jobs:
 
     - name: Build ISO
       run: |
-        buildiso -p antergos
+        ./buildiso -p antergos
 
     - name: Upload ISO artifact
       uses: actions/upload-artifact@v4

iso-profiles/common/common.yaml

@@ -50,6 +50,8 @@ packages-base:
   - which
   - xfsprogs
   - zsh
+  - jack2
+  - noto-fonts-emoji
 packages-apps:
   - powertop
   - inxi