DeprecationWarning: the load_module() method is deprecated and slated for removal in Python 3.12; use exec_module() instead

[mgor]

When running the unit tests and looking at the output, the DeprecationWarning in the title is thrown/visible a couple of times.

In python 3.4 load_module was replaced with exec_module. [0][1]

Deprecated since version 3.4: The recommended API for loading a module is exec_module() (and create_module()). Loaders should implement it instead of load_module(). The import machinery takes care of all the other responsibilities of load_module() when exec_module() is implemented.

The tests does indeed work on 3.12, so seems like it hasn't been removed yet,
but this PR replaces the call to load_module in locust.util.load_locustfile.load_locustfile to use exec_module instead.

[0] https://peps.python.org/pep-0451/
[1] https://docs.python.org/3/library/importlib.html#importlib.abc.Loader.load_module

[cyberw]

Awesome. I've been annoyed by this for a long time. Will sure to merge this once the modern-UI-default is released.