Add support for free-threading/No-GIL

[daveisfera]

Summary

GIL is enabled when using a free-threading build of 3.14

<frozen importlib._bootstrap>:491: RuntimeWarning: The global interpreter lock (GIL) has been enabled to load module 'newrelic.packages.wrapt._wrappers', which has not declared that it can run safely without the GIL. To override this behavior and keep the GIL disabled (at your own risk), run with PYTHON_GIL=0 or -Xgil=0.

Desired Behavior

GIL would remain disabled

Possible Solution

Not sure if changes need to be made to the code, but in the minimum the newrelic module needs to declare that it's safe without the GIL so it won't be automatically disabled.

Additional context

We're looking to move to run with free-threading to improve performance in our parallel workers and this is preventing it.

[Newrelic-Boomi]

https://new-relic.atlassian.net/browse/NR-478802

[hmstepanek]

@TimPansino Looked into this and it doesn't look too difficult to do. I'm assigning this to Tim to add support for this.

[hmstepanek]

We have merged the PR for this into main-just need to release it.