ci: use shared action for merge-by updates

[traeok]

Proposed changes

Marking as draft until zowe-actions/shared-actions#33 is merged

Release Notes

Milestone:

Changelog:

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• Enhancement (non-breaking change which adds or improves functionality)
• Breaking change (a change that would cause existing functionality to not work as expected)
• Documentation (Markdown, README updates)
• Other (please specify above in "Proposed changes" section)

Checklist

General

• I have read the CONTRIBUTOR GUIDANCE wiki
• All PR dependencies have been merged and published (if applicable)
• A GIF or screenshot is included in the PR for visual changes
• The pre-publish command has been executed:
  • v2 and below: yarn workspace vscode-extension-for-zowe vscode:prepublish
  • v3: pnpm --filter vscode-extension-for-zowe vscode:prepublish

Code coverage

• There is coverage for the code that I have added
• I have added new test cases and they are passing
• I have manually tested the changes

Deployment

• I have added developer documentation (if applicable)
• Documentation should be added to Zowe Docs
  • If you're an outside contributor, please post in the #zowe-doc Slack channel to coordinate documentation.
  • Otherwise, please check with the rest of the squad about any needed documentation before merging.
• These changes may need ported to the appropriate branches (list here):

Further comments

[zFernand0]

Looks a lot simpler,
Thanks for moving the action to the shared-actions repo 🙏