Automate updating release manager and release issue on the project website

[gaiksaya]

Is your feature request related to a problem? Please describe

Update release manager and release issue on the project website as soon as release manager is assigned to the release issue.
Currently, the release manager or someone needs to go and raise a PR manually Example:opensearch-project/project-website#3229

Describe the solution you'd like

As soon as release manager is assigned to the release issue, raise a PR automatically towards project website repo.

Describe alternatives you've considered

Raise the PR manually

Additional context

No response