support fips compliance by replacing md5 with sha256

[actionjax]

Hello, we work on fips compliant systems and superset will not work unless all the hashes are replaced with encryption stronger than md5. Can superset be modified to use sha256? I think it should be as simple as replacing all md5() calls with sha256(). Notably the uuid generation (key_value/utils.py) is the source of the compliant. I can work on a PR on my spare time if desired.

[rusackas]

Closing this issue since it's a feature request more than a bug. We're still hopeful that the PR can be picked up by a volunteer, but in the meantime, we're trying to whittle the Issues backlog to bugs only, so we'll close this. Thanks for the contributions!

[mamccorm]

Some of these are related to dependencies? Filed PRs:

• feat: Updating Hashing Method to PBKDF2 with SHA-256 dpgaspar/Flask-AppBuilder#2234
• Update to use sha256 instead of md5 pallets-eco/flask-caching#563