[CES-12] Added a Keep Alive action to keep the repository active when it contains cron actions

[mamu0]

List of changes

Added keep-alive action and keep_alive_repository workflow

Motivation and context

If there are actions in a repository that work with a trigger schedule, GitHub will disable them after 60 days if there have been no commits in the repo, in this way we have a workflow that checks every day if 59 days have passed, if so, it does an empty push to revitalize the repository, otherwise it does nothing.

Type of changes

• [x] Add new resources
• [ ] Update configuration to existing resources
• [ ] Remove existing resources

Does this introduce a change to production resources with possible user impact?

• [ ] Yes, users may be impacted applying this change
• [x] No

Other information

[gunzip]

lgtm, let's wait for other's comments