gt4py update: fix GCC 12/13 compiler flags

[romanc]

Description

Propagate Cxx flags that work both with GCC 12 and 13. This is a fixup from PR #399.

How has this been tested?

GT4Py changes have been tested locally.

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas: N/A
• I have made corresponding changes to the documentation (e.g. add new modules to docs/docstrings/): N/A
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules
• New check tests, if applicable, are included: N/A

[FlorianDeconinck]

👍