Fix input completion tests on Qt6 & run tests on 22.04 (#4774)

* Tests: Fix InputCompletion tests in Qt6

This is achieved by not checking exact order for certain completion tests

* Tests: Use Ubuntu 22.04 for all tests

This allows us to be a bit more loose and use more C++20 features in
tests

* Update dockerfiles

.github/workflows/test.yml

@@ -20,9 +20,9 @@ jobs:
     strategy:
       matrix:
         include:
-          - os: "ubuntu-20.04"
+          - os: "ubuntu-22.04"
             qt-version: "5.15.2"
-          - os: "ubuntu-20.04"
+          - os: "ubuntu-22.04"
             qt-version: "5.12.12"
           - os: "ubuntu-22.04"
             qt-version: "6.2.4"
@@ -44,6 +44,12 @@ jobs:
           modules: ${{ env.QT_MODULES }}
           version: ${{ matrix.qt-version }}
 
+      - name: Apply Qt patches (Ubuntu)
+        if: startsWith(matrix.os, 'ubuntu') && startsWith(matrix.qt-version, '5.')
+        run: |
+          patch "$Qt5_DIR/include/QtConcurrent/qtconcurrentthreadengine.h" .patches/qt5-on-newer-gcc.patch
+        shell: bash
+
       # LINUX
       - name: Install dependencies (Ubuntu)
         if: startsWith(matrix.os, 'ubuntu')