Update elastic-managed-llm.md (#225108)

Remove the early access form since we started rolling out.

## Summary

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gif.


### Checklist

Check the PR satisfies following conditions. 

Reviewers should verify this PR satisfies this list as well.

- [ ] Any text added follows [EUI's writing
guidelines](https://elastic.github.io/eui/#/guidelines/writing), uses
sentence case text and includes [i18n
support](https://github.com/elastic/kibana/blob/main/src/platform/packages/shared/kbn-i18n/README.md)
- [ ]
[Documentation](https://www.elastic.co/guide/en/kibana/master/development-documentation.html)
was added for features that require explanation or tutorials
- [ ] [Unit or functional
tests](https://www.elastic.co/guide/en/kibana/master/development-tests.html)
were updated or added to match the most common scenarios
- [ ] If a plugin configuration key changed, check if it needs to be
allowlisted in the cloud and added to the [docker
list](https://github.com/elastic/kibana/blob/main/src/dev/build/tasks/os_packages/docker_generator/resources/base/bin/kibana-docker)
- [ ] This was checked for breaking HTTP API changes, and any breaking
changes have been approved by the breaking-change committee. The
`release_note:breaking` label should be applied in these situations.
- [ ] [Flaky Test
Runner](https://ci-stats.kibana.dev/trigger_flaky_test_runner/1) was
used on any tests changed
- [ ] The PR description includes the appropriate Release Notes section,
and the correct `release_note:*` label is applied per the
[guidelines](https://www.elastic.co/guide/en/kibana/master/contributing.html#kibana-release-notes-process)

### Identify risks

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Describe the risk, its severity, and mitigation for each identified
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- [ ] [See some risk
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- [ ] ...

Co-authored-by: István Zoltán Szabó <szabosteve@gmail.com>

docs/reference/connectors-kibana/elastic-managed-llm.md

@@ -24,6 +24,3 @@ Only request metadata is logged in AWS CloudWatch.
 No information related to prompts is retained.
 Logged metadata includes the timestamp, model used, region, and request status.
 
-## Early access
-
-Early access is available by submitting the form provided [here](https://forms.gle/o1AwPMVYMziHbom28).