CI: use Qt ubuntu package on Linux

Author: HuguesDelorme

.github/workflows/ci_linux.yml

@@ -6,22 +6,21 @@ jobs:
     build-linux:
         strategy:
             matrix:
-                qt_version: [5.15.2, 6.5.2]
+                qt_version_major: [5, 6]
                 os: [ubuntu-latest, ubuntu-24.04-arm]
 
         runs-on: ${{matrix.os}}
-        name: build-${{matrix.os}}-qt${{matrix.qt_version}}
+        name: build-${{matrix.os}}-qt${{matrix.qt_version_major}}
 
         steps:
         - name: Checkout
           uses: actions/checkout@v2
 
         - name: Install Qt
-          uses: jurplel/install-qt-action@v3
-          with:
-              version: ${{matrix.qt_version}}
-              cache: true
-              cache-key-prefix: QtCache
+          run: |
+              sudo apt-get -y install \
+                  qtbase${{matrix.qt_version_major}}-dev \
+                  libqt${{matrix.qt_version_major}}svg${{matrix.qt_version_major}}-dev
 
         # Actually needed for Qt6
         - name: Install dependencies for "xcb" Qt plugin