Change node 12 to node 16 to avoid Github Actions deprecation warnings

[madalozzo]

Warning in Github Actions:
Node.js 12 actions are deprecated. For more information see: https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/. Please update the following actions to use Node.js 16: RocketChat/Rocket.Chat.GitHub.Action.Notification

I have modified the action.yaml to use node16 runtime instead node12. I've tested the modifications creating a new release in my repository and everything is working

[CLAassistant]

All committers have signed the CLA.

[UzaeirAzhar]

This PR solves #8

[madalozzo]

While PR is not approved, you can use from my own repository:

      - name: Rocket.Chat Notification
        uses: madalozzo/Rocket.Chat.GitHub.Action.Notification@v1
        timeout-minutes: 2
        continue-on-error: true
        if: always()
        with:
          ...