ci: Fix building

Author: j-ulrich

.github/workflows/ci.yml

@@ -16,7 +16,7 @@ jobs:
                 /bin/bash -c "
                 cd /workspace
                 && g++ --version
-                && qmake --version
+                && qmake6 --version
                 && cd tests
                 && mkdir _build
                 && cd _build