Wrong RegExp for XACML <Policy ...> ... </Policy>

[NisonChrist]

ReBAC-Project-Code-Python/datasets/process.py

Line 43 in 6b37cb6

policy_pattern = re.compile(r"<Policy[\s\S]*?<\/Policy>")

We should match ''<Policy[[A SPACE]]...>...</Policy>'', rather than ''<Policy...>...</Policy>''.