use correct runner for every arch

.github/workflows/linux-flatpak.yml

@@ -26,18 +26,18 @@ jobs:
   flatpak:
     name: "Build flatpak"
     needs: [get-version]
-    runs-on: ubuntu-latest
     container:
       image: ghcr.io/flathub-infra/flatpak-github-actions:freedesktop-25.08
       options: --privileged
     strategy:
-      #fail-fast: false
+      fail-fast: false
       matrix:
         variant:
           - arch: x86_64
             runner: ubuntu-24.04
-          #- arch: aarch64
-          #  runner: ubuntu-24.04-arm
+          - arch: aarch64
+            runner: ubuntu-24.04-arm
+    runs-on: ${{ matrix.variant.runner }}
     steps:
       - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
         with:
@@ -57,19 +57,19 @@ jobs:
             type: git
                     path: cryptomator
                     commit: ${{ github.sha }}
+      - name: Copy build script for upload
+        run: cp org.cryptomator.Cryptomator.yaml org.cryptomator.Cryptomator.${{matrix.variant.arch}}.yaml
       - uses: actions/upload-artifact@bbbca2ddaa5d8feaa63e36b76fdaad77386f024f # v7.0.0
         with:
           archive: false
           if-no-files-found: error
           path: |
-            org.cryptomator.Cryptomator.yaml
+            org.cryptomator.Cryptomator.${{matrix.variant.arch}}.yaml
       - uses: flatpak/flatpak-github-actions/flatpak-builder@92ae9851ad316786193b1fd3f40c4b51eb5cb101 # v6.6
         with:
           bundle: cryptomator.flatpak
           manifest-path: org.cryptomator.Cryptomator.yaml
           cache-key: flatpak-builder-${{ github.sha }}
-          #build-dir: flatpak_app
-          #gpg-sign:
           arch: ${{ matrix.variant.arch }}
 
   tarball: