[Serve][Doc] Update the doc code to use new api

[sihanwang41]

Signed-off-by: Sihan Wang [email protected]

Why are these changes needed?

Related issue number

Closes #27436

Checks

• [ ] I've signed off every commit(by using the -s flag, i.e., git commit -s) in this PR.
• [ ] I've run scripts/format.sh to lint the changes in this PR.
• [ ] I've included any doc changes needed for https://docs.ray.io/en/master/.
• [ ] I've made sure the tests are passing. Note that there might be a few flaky tests, see the recent failures at https://flakey-tests.ray.io/
• Testing Strategy
  • [ ] Unit tests
  • [ ] Release tests
  • [ ] This PR is not tested :(

[edoakes]

@sihanwang41 as part of this, can you also please make sure that all of the code samples are being tested in CI?

[simon-mo]

there's a merge conflict with rllib.md from @zcin's PR

[sihanwang41]

rebased

[edoakes]

@sihanwang41 looks good, but there were a lot of test failures. I think it's unlikely to be related and possibly fixed on master, could you merge and push to retrigger CI?