feat: `add-to-cc-board` Github action created.

[ChrisChV]

Description

• This is a label trigger to add an Issue or PR to the edx-platform Core Contributor project board.
• This action uses the Core Contributor assignee label as a trigger.
• This action reuses https://github.com/openedx/.github/pull/169#issue-3061448385
• When you add the label to an issue or PR, it is automatically added to the board https://github.com/orgs/openedx/projects/79
• See this document for more technical info
• Which edX user roles will this change impact? "Developer".
• It is necessary to create an organization secret called PROJECTS_TOKEN with a Github token with these scopes: read:org, project (Created in: https://github.com/openedx/axim-engineering/issues/1523)

Supporting information

• Github issue: https://github.com/openedx/wg-coordination/issues/157
• Epic: https://github.com/openedx/wg-coordination/issues/138
• Internal ticket: SE-6387

Testing instructions

• There is no way to test this in the organization without being merged, but you can test this same code in a sandbox:
  • repo-edx
  • .github sandbox
  • Sandbox board

Testing on the sandbox

• The reusable action in the sandbox is configured in .github sandbox. The same for the openedx org is already configured and merged: https://github.com/openedx/.github/pull/169
• The action for the trigger in the sandbox is configured in repo-edx
• The board in the sandbox is https://github.com/orgs/ChrisChV-Sandbox-Organization/projects/1
• Create an issue in repo-edx.
• Add the Core Contributor assignee label. Verify that the issue is added to the board https://github.com/orgs/ChrisChV-Sandbox-Organization/projects/1
• Create a PR in repo-edx.
• Add the Core Contributor assignee label. Verify that the PR is added to the board https://github.com/orgs/ChrisChV-Sandbox-Organization/projects/1

Deadline

None

Other information

• [X] It is necessary to create an organization secret called PROJECTS_TOKEN with a Github token with these scopes: read:org, project (Created in: https://github.com/openedx/axim-engineering/issues/1523)