Support FIPS enabled machines with MD5 hashing

[MattTheCuber]

FIPS enabled machines prohibit MD5 hashing for security reasons. Using hashlib.md5 in Python will throw the error ValueError: [digital envelope routines] unsupported. There are typically 2 resolutions to this problem: use the usedforsecrutiy=False flag or use SHA1 hashing. The usedforsecurity flag is easier to implement and was introduced in Python 3.9, which is the minimum Python version for this library, so that is the method I chose.

[github-actions]

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