don't run tests in parallel

Author: vintagepc

.github/workflows/tests.yml

@@ -66,7 +66,7 @@ jobs:
       run: cd ${{ runner.workspace }}/MINI404/build && ninja
 
     - name: Run QTest
-      run: cd ${{ runner.workspace }}/MINI404/build && make check-qtest-buddy -j4
+      run: cd ${{ runner.workspace }}/MINI404/build && make check-qtest-buddy
 
     - name: Upload log
       if: failure()