Exception when FIPS enabled

[diacristian]

Hello,

When FIPS is enabled on computer registry, we get an exception when trying to log in.

The fix would require to change, in a future version, in OAuthFlowImpl :: getHash, the SHA256Managed instantiation with SHA256CryptoServiceProvider.

[timothodge]

Hello @diacristian,

Thanks for raising the issue. The contributors will try to get to this, but you can also make your own PR for review if you would like to try and get this into a new version sooner. Hope you have a great day!