Issue #434: Fix autoamp init wrapper compatibility

[karthik-ravi-1537]

This PR addresses an issue with the autoamp_init_wrapper function that patches PyTorch's torch.autocast.init method.

Changes:

• Changed the function call to the torch.autocast.init (or other functions that are patched) to have the expected function signature.
• Replaced deprecated torch.get_autocast_cpu_dtype() with the recommended torch.get_autocast_dtype('cpu')
• Added tests for the autoamp_init_wrapper function in tests/test_autocast_patch.py.

[karthik-ravi-1537]

Relates to Issue #434