Fix PyYAML 6+ compatibility by using SafeLoader

[rishihg]

Summary

This PR updates pytic.py to use yaml.SafeLoader when loading YAML configuration files.

Background

• In PyYAML < 5.1, yaml.load() without a Loader argument was allowed.
• In PyYAML ≥ 6.0 (now required for Python 3.12+), yaml.load() requires an explicit Loader.
• Without this change, importing configurations with PyTic raises:

TypeError: load() missing 1 required positional argument: 'Loader'

Fix

Replaced:

cfg = yaml.load(ymlfile)

with:

cfg = yaml.load(ymlfile, Loader=yaml.SafeLoader)

Benefits

Restores compatibility with PyYAML 6+ and Python 3.12+

Backward compatible with older PyYAML

Prevents runtime errors for users on modern environments

Notes

This is a minimal change, does not affect any existing functionality, and follows PyYAML’s recommendation for safe parsing.