Add GitHub action to notify Slack on star of repo

[Lee Calcote]

Description:
When someone stars this repo, it is encouraging to the community of contributors when a notification is received in the community slack workspace.

Implementation:
Using this slack.yaml (GitHub Action) as an example to copy directly from, create a .github/workflows folders, copy and modify the slack.yaml file to suite this repo.

[ninja]

I'd like to work on this kindly assign me.