Minor JWT build improvements

[sberyozkin]

This PR:

• Deprecates a number of builder API methods and introduces more compact alternatives.

  For example, when we do:
  Jwt.claims("somejson.json").jws().signatureKeyId("kid").sign(), signature in signatureKeyId is duplicating what both jws() and sign imply. Similarly for all other deprecated methods. The IDE also helps with algorithm related methods, for ex, when we do jws().algorithm(...) we see a SignatureAlgorithm parameter type.

  In fact, originally I did plan for Jwt.claims("somejson.json").jws().keyId("kid").sign() - the compactness of the API is a big priority, but then I somehow got offtrack when I was looking at the inner token case, where the token is signed and encrypted:

Jwt.claims().jws().keyId().innerSign().keyId().encrypt();

Here I thought well, 2 keyId(), 1st one sets a key if of the signing key, 2nd one - of the key encryption key.
But over time I've come to the conclusion that this case is quite advanced, the mainstream case is sign and in this advanced case, after the formatting, it also becomes more readable. kids will likely be configurable too.

• deprecated none for the innerSign() - I came to this conclusion while doing the initial MP JWT PR, it is basically useless :-) to have encrypt() with an internal none as it does not add anything to the encrypt only case, i.e, it does not help with identifying who signed it. It also makes it hard to spot if the user made a typo in the config property

All of these deprecated methods/properties will be dropped in 3.0.0

• config property support for exp and issuer - these are the only 2 claims that are required by MP JWT, so it will make much easier to test, every time I see a custom exp being set in the code I'm thinking, oh, we need to get it configured.

[MikeEdgar]

A few comments, looks good overall.

[radcortez]

Just a recommendation to complete the deprecated tag, but not a blocker imo.

[sberyozkin]

Hi @MikeEdgar @radcortez thanks, will deal with the comments

[sberyozkin]

@MikeEdgar @radcortez I think I've addressed all the comments, cheers

[MikeEdgar]

LGTM

[sberyozkin]

Hi Mike thanks, I've realized I forgot to update the docs (also updated the text related to the previous changes in sync with the similar Quarkus text, @bobbyphilip - minor update around the key properties to clarify when they are effective) - please check, I can merge later this evening if there will be no comments but if some wording/grammar can be improved then it will be fine.
CC @radcortez

[sberyozkin]

@radcortez Thanks, I'll do another couple of minor updates :-)

[sberyozkin]

Merging now as it has already been approved a few times, updated the text to refer to a key only as opposed to a public key or private key.