gha: build - test ubuntu on ARM (apt Qt install)

Author: codeling

.github/workflows/build.yml

@@ -46,7 +46,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [macos-13, ubuntu-latest, ubuntu-20.04, windows-latest]
+        os: [macos-13, ubuntu-latest, ubuntu-20.04, ubuntu-24.04-arm, windows-latest]
 
     steps:
 
@@ -105,7 +105,8 @@ jobs:
 #      run: |
 #        echo "OPENIA_CMAKE_OPTIONS=${{env.OPENIA_CMAKE_OPTIONS}} -DOpenMP_CXX_FLAGS=\"-Xpreprocessor -fopenmp -lomp\" -DOpenMP_CXX_INCLUDE_DIR=\"/opt/homebrew/opt/libomp/include\" -DOpenMP_libomp_LIBRARY=\"/opt/homebrew/opt/libomp/lib/libomp.dylib\"" >> "$GITHUB_ENV"
 
-    - name: Qt install
+    - if: matrix.os != 'ubuntu-24.04-arm'
+      name: Qt install
       # see https://github.com/marketplace/actions/install-qt for details
       uses: jurplel/install-qt-action@v4
       with:
@@ -115,6 +116,12 @@ jobs:
         cache: true
         cache-key-prefix: Qt
 
+    - if: matrix.os != 'ubuntu-24.04-arm'
+      name: Qt: install (Ubuntu ARM)
+      run: |
+        sudo apt update && sudo apt install libgl1-mesa-dev libxt-dev libxt-dev libxcursor-dev libsdl2-dev qt6-base-dev qt6-tools-dev qt6-svg-dev
+        echo "QT_VERSION=$(/usr/bin/dpkg -s qt6-base-dev | /usr/bin/grep 'Version' | /usr/bin/awk '{ split($2, a, "+"); print a[1]; }')" >> "$GITHUB_ENV"
+
     ##################################################################
     # VR: OpenXR, OpenVR, boost