Fix flexparser FIPS mode

[MattTheCuber]

With FIPS mode the following error is thrown.
ValueError: [digital envelope routines: EVP_DigestInit_ex] disabled for FIPS

Also, do I need to update anything here or is that pulled in?

[coveralls]

Pull Request Test Coverage Report for Build 7892561388

Details

• 0 of 1 (100.0%) changed or added relevant line in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 88.165%

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Totals
Change from base Build 7470425156:	0.0%
Covered Lines:	663
Relevant Lines:	752

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💛 - Coveralls

[hgrecco]

Thanks for the PR. I will update Pint. I might be putting this (and other vendored packages) as a dependencies as vendoring complicates things for the maintainers of linux distros.

By the way, just as a curiosity, how did you spot this. I have not seen this problem in any platform.

[MattTheCuber]

We use a FIPS enabled RHEL 8 machine

[MattTheCuber]

@hgrecco

Any estimate on when this will be updated in Pint?

Also, a note: this fix only works on Python 3.9+. I have another solution if you require support for earlier versions of Python.

[MattTheCuber]

@hgrecco sorry to ping again ^

[hgrecco]

done in 0.3.1 (let me know if it works for you)

[MattTheCuber]

Great. I manually tested and it worked for me. However, I can't test this until it's released in Pint here.