Remove preview and switch to latest accept headers

[bitwiseman]

Description

Fixes #1143

Before submitting a PR:

• [ ] Changes must not break binary backwards compatibility. If you are unclear on how to make the change you think is needed while maintaining backward compatibility, CONTRIBUTING.md for details.
• [ ] Add JavaDocs and other comments explaining the behavior.
• [ ] When adding or updating methods that fetch entities, add @link JavaDoc entries to the relevant documentation on https://docs.github.com/en/rest .
• [ ] Add tests that cover any added or changed code. This generally requires capturing snapshot test data. See CONTRIBUTING.md for details.
• [ ] Run mvn -D enable-ci clean install site locally. If this command doesn't succeed, your change will not pass CI.
• [ ] Push your changes to a branch other than main. You will create your PR from that branch.

When creating a PR:

• [ ] Fill in the "Description" above with clear summary of the changes. This includes:
  • [ ] If this PR fixes one or more issues, include "Fixes #" lines for each issue.
  • [ ] Provide links to relevant documentation on https://docs.github.com/en/rest where possible. If not including links, explain why not.
• [ ] All lines of new code should be covered by tests as reported by code coverage. Any lines that are not covered must have PR comments explaining why they cannot be covered. For example, "Reaching this particular exception is hard and is not a particular common scenario."
• [ ] Enable "Allow edits from maintainers".

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 80.79%. Comparing base (8d6964d) to head (6d90891). Report is 14 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1859 +/- ## ============================================ - Coverage 81.04% 80.79% -0.25% + Complexity 2418 2417 -1 ============================================ Files 233 233 Lines 7349 7264 -85 Branches 398 398 ============================================ - Hits 5956 5869 -87 Misses 1148 1148 - Partials 245 247 +2 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.