[ci] replace faulty from url pip install with extras

.ci/gitlab/test_pip_installed.bash

@@ -12,7 +12,12 @@ PIP_CLONE_URL="git+${CI_PROJECT_URL}@${CI_COMMIT_SHA}"
 # source /tmp/venv/bin/activate
 pip install ${PIP_CLONE_URL}
 pip uninstall -y pymor
-pip install ${PIP_CLONE_URL}#egg=pymor[full]
+
+# this is currently disabled because it erroneously pulls in pyqt5
+# pip install ${PIP_CLONE_URL}#egg=pymor[full]
+# pip uninstall -y pymor
+
+pip install .[full]
 pip uninstall -y pymor
 # other requirements are installed from pymor[full]
 pip install -r requirements-ci.txt