Use Flatpak of flatpak-builder so that we use latest build

Signed-off-by: Matthew J. Milner <[email protected]>

.github/workflows/flatpak.yml

@@ -14,6 +14,9 @@ jobs:
     - name: Configure flatpak
       run: flatpak remote-add --if-not-exists --user flathub https://dl.flathub.org/repo/flathub.flatpakrepo
 
+    - name: Install flatpak-builder
+      run: flatpak --user install --or-update --noninteractive flathub org.flatpak.Builder
+
     - name: Configure git
       run: git config --global protocol.file.allow always
       # Have to do this because for a while git's handling of submodules was broken
@@ -81,7 +84,7 @@ jobs:
       run: mv openchemistry/avogadroapp/flatpak/org.openchemistry.Avogadro2.yaml ./
 
     - name: Build with flatpak-builder
-      run: flatpak-builder --force-clean --user --install-deps-from=flathub --arch=x86_64 --default-branch=test --repo=repo builddir org.openchemistry.Avogadro2.yaml
+      run: flatpak run org.flatpak.Builder --force-clean --user --install-deps-from=flathub --arch=x86_64 --default-branch=test --repo=repo builddir org.openchemistry.Avogadro2.yaml
 
     - name: Create bundle
       run: flatpak build-bundle repo Avogadro2.flatpak org.openchemistry.Avogadro2 test