pass GITHUB_TOKEN for cargo binstall for per-ip rate limit

[anatawa12]

In some case, cargo binstall will face API per-ip rate limit on github actions runner (due to shared ip address).

As a solution, I want install-action to have an feature to pass github.token to cargo binstall as a GITHUB_TOKEN environment variable or parameter.

https://github.com/vrc-get/vrc-get/actions/runs/9664217883/job/26658335596#step:7:1

As a workaround, we can specify env: { GITHUB_TOKEN: ${{ github.token }} }

[taiki-e]

See https://github.com/taiki-e/install-action/issues/556 for the previous discussion.