Ideally you don't ever rely on CI specific automation tooling to actually accomplish anything and instead just use it as a dumb "not my dev machine" to execute workflows.

You should always engineer things so you can fall back to something akin to:

./scripts/deploy_the_things

Ideally backed by a real build system and task engine ala Bazel, Gradle, whatever else floats your boat.

It also means you are free to move between different runners/CI providers and just have to work out how to re-plumb secrets/whatever.

GH actions/friends really provide minimal value, the fact they have convinced everyone that encoding task graphs into franken-YAML-bash is somehow good is one of the more egregious lies sold to the development community at large.

Well, git ops might not be impacted on Github, usual Github outages tend to be through Actions/the site, not the actual git operations. Doesn't seem like you can use a local copy but you can use Gitbucket/Gitlab.