add experimental aarch64 build to CI

.github/workflows/build_all.yml

@@ -277,6 +277,28 @@ jobs:
               name: sdrpp_debian_bookworm_amd64
               path: ${{runner.workspace}}/sdrpp_debian_amd64.deb
 
+    build_debian_bookworm_aarch64:
+        runs-on: ubuntu-24.04-arm
+
+        steps:
+        - uses: actions/checkout@v4
+
+        - name: Create Docker Image
+          run: cd $GITHUB_WORKSPACE/docker_builds/debian_bookworm && docker build . --tag sdrpp_build
+
+        - name: Run Container
+          run: docker run --name build -v $GITHUB_WORKSPACE:/root/SDRPlusPlus --env BUILD_NO="-$GITHUB_RUN_NUMBER" sdrpp_build /root/do_build.sh
+
+        - name: Recover Deb Archive
+          working-directory: ${{runner.workspace}}
+          run: docker cp build:/root/SDRPlusPlus/sdrpp_debian_amd64.deb ./
+
+        - name: Save Deb Archive
+          uses: actions/upload-artifact@v4
+          with:
+              name: sdrpp_debian_bookworm_aarch64
+              path: ${{runner.workspace}}/sdrpp_debian_amd64.deb
+
     build_debian_sid:
         runs-on: ubuntu-latest