This is initial implementation of op-cli-installer.

Typescript code from install-cli-action is copied to this repo as it is, without any changes. Only exported function installCliOnGithubActionRunner doesn't handle errors to allows end users to handle errors in their way.
The code is placed inside github-action module, to identify that this code is only applicable for github actions. This also allows to extend this repo in the future if we would need to install CLI in other scenarios.

Exported installCliOnGithubActionRunner - the main function that installs the CLI on github runners. Along with ReleaseChannel and VersionResolver - they are not used as exported pieces. But as now this repo is a library, I think this is beneficial to export those entries as well.

For now we do not build and publish an NPM package with this code. We'll install it as dependency in install-cli-action and load-secrets-action directly from github.

Implementation steps

1. Init project and setup: Jest, lint-staged, eslint, prettier, husky
2. Add github action job that lints, formats, tests and type checks the code. Also another job checks signed commits.
3. Copied code from install-cli-action

How to test

1. Unit tests are passing in pipeline
2. Code from this repo is used as dependency in install-cli-action PR, that has integration tests. As you can see pipeline in this PR is passing, confirming that action works well and can install CLI on different runners (linux, windows and macos) using this repo as dependency.