Updated changelog to point at issue not PR

[telday]

What does this PR do?

Update reference in changelog to reference an issue in place of the pull request.

What ticket does this PR close?

Resolves #2086

Checklists

Change log

• The CHANGELOG has been updated, or
• This PR does not include user-facing changes and doesn't require a CHANGELOG update

Test coverage

• This PR includes new unit and integration tests to go with the code changes, or
• The changes in this PR do not require tests

Documentation

• Docs (e.g. READMEs) were updated in this PR, and/or there is a follow-on issue to update docs, or
• This PR does not require updating any documentation

API Changes

• The OpenAPI spec has been updated to meet new API changes (or an issue has been opened), or
• The changes in this PR do not affect the Conjur API