Add new assert_equal test util based on torch.testing.assert_close (#3872)

Co-authored-by: Philip Meier <github.pmeier@posteo.de>

test/_assert_utils.py

+"""This is a temporary module and should be removed as soon as torch.testing.assert_equal is supported."""
+# TODO: remove this as soon torch.testing.assert_equal is supported
+
+import functools
+
+import torch.testing
+
+__all__ = ["assert_equal"]
+
+
+assert_equal = functools.partial(torch.testing.assert_close, rtol=0, atol=0)