Upgrade http4k to v6, JDK and Gradle

[daviddenton]

No description provided.

[p8]

Hey @daviddenton,

Unrelated to this PR, but it seems http4k has more than 10 test mutations, which is no longer allowed:

The number of test mutations will be limited to 10. We do not mind if you open up pull requests between runs to try out various mutations for your framework so long as the total number at any given time does not exceed 10.

#8420

[daviddenton]

Hey @daviddenton,

Unrelated to this PR, but it seems http4k has more than 10 test mutations, which is no longer allowed:

The number of test mutations will be limited to 10. We do not mind if you open up pull requests between runs to try out various mutations for your framework so long as the total number at any given time does not exceed 10.

#8420

OK - we'll look at removing some soon. Thanks for pointing it out. 🙃

[daviddenton]

Hey @daviddenton,

Unrelated to this PR, but it seems http4k has more than 10 test mutations, which is no longer allowed:

The number of test mutations will be limited to 10. We do not mind if you open up pull requests between runs to try out various mutations for your framework so long as the total number at any given time does not exceed 10.

#8420

@p8 As promised #9676 🙃

[msmith-techempower]

Well, I confirmed that http4k-helidon-jdbc works on main, but is indeed breaking after this PR's changes.

[daviddenton]

yep - I'm not sure what's going on with this. I'll look at it soon. Feel free to close the PR off until I get a chance to look at it 🙃