docs: updates for client secret rotation

[unatasha8]

This PR replaces PR https://github.com/ory/docs/pull/2424/changes

Feature PR: ory/hydra#4063
Docs updates for client secret rotation

Checklist

• [ X] I have read the contributing guidelines and signed the CLA.
• I have referenced an issue containing the design document if my change introduces a new feature.
• [ X] I have read the security policy.
• [X ] I confirm that this pull request does not address a security vulnerability.
  If this pull request addresses a security vulnerability,
  I confirm that I got approval (please contact security@ory.com) from the maintainers to push the changes.
• I have added tests that prove my fix is effective or that my feature works.
• I have added the necessary documentation within the code base (if appropriate).

[alnr]

beautiful!