Add TokenHash and Label to AuthToken, allow revoke by hash

[neelvirdy]

Implements Phase 1/4 of #343, which tracks the switch to only store hashes of API Tokens in DB.

The end-user experiences no change in behavior from this PR, but newly created tokens will have a TokenHash and Label stored in DB. The Label is an arbitrary string that does not need to be unique, but allows the user to track the keys that are in use and know which to revoke when needed.

Allowing revoke by hash is necessary to ensure keys can still be revoked after we stop storing the raw token itself.

For info on follow-up PRs to complete the switch, see the issue linked above.

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Demonstrating creating a new key with a label, as well as revoking keys by hash and by key. The listed tokens with the censored token are the keys that have no token value stored in the db, and are being revoked via their hash.

Screen.Recording.2022-11-07.at.12.08.59.PM.mov

[en0ma]

@neelvirdy can the label address this requirement #471 ?

[neelvirdy]

@neelvirdy can the label address this requirement #471 ?

@en0ma yep! didn't see that issue till now but it seems identical except these 2 differences:

1. Label vs name for field name - i have no strong preference with which way we go. Label is slightly more intuitive to me but clearly not for everyone! I don't see any convention from a quick google search. Open to adjusting it if someone shouts
2. I intend to make the label a required input when generating a key, so the user is encouraged to provide a meaningful label and remember what the key is for, rather than auto-generating a random label and relying on the user to do their due diligence proactively to have good key management.

[en0ma]

2. I intend to make the label a required input when generating a key, so the user is encouraged to provide a meaningful label and remember what the key is for, rather than auto-generating a random label and relying on the user to do their due diligence proactively to have good key management.

If this is done, I think it will completely address that issue. I am ok with using "label" too.

[en0ma]

@alvin-reyes can you have a look at this PR

[alvin-reyes]

Great work @neelvirdy!

Can you add some verification tests and post it in this PR? Just add a new section on the description part

## Verification 
### revoke user by hash
<screen shot of the UI or the cli>
### revoke user by key
<screen shot of the UI or the cli>

[alvin-reyes]

LGTM