Feature Request: Install Only Mode

[rocktavious]

Lots of different github actions out there offer actions to install the CLI tools (along with caching support) so that you can make it easier to use the binary in subsequent steps of a job.

Example

- name: Install kubectl
  uses: azure/setup-kubectl@v4
  with:
    version: 'v1.33.0'

- name: Use Kubectl
  run: |
    kubectl get nodes

Another

- name: Install Task
  uses: go-task/setup-task@v1

- name: Use Task
  run: |
    task setup

It would be helpful if this action also provided an "install only" mode that installs (and caches) the tailscale binary so you can use it in followup steps. Right now it tries to ALWAYS login.