Ensure GCC 10.3.1 Compatibility

Qt 6.10 continues to support GCC 10, and several major LTS distributions, including RHEL 8, openSUSE 15.5, and Debian 11, still rely on this compiler version. Given the long-term relevance of RHEL 8, dropping GCC 10 support is not currently an option.

Jenkins packaging also uses the same build machines as QtCreator (GCC 10.3.1)