ci: integrate "GitHub Script" Action in Stark

[SuperITMan]

I'm submitting a...

[ ] Regression (a behavior that used to work and stopped working in a new release)
[ ] Bug report  
[X] Feature request
[ ] Documentation issue or request
[ ] Support request => Please do not submit support request here, instead see https://github.com/NationalBankBelgium/stark/blob/master/CONTRIBUTING.md#got-a-question-or-problem

Current behavior

There is no bot on Stark repo.

Expected behavior

Adding a bot can help to manage issues, PRs, etc.

Some examples we could implement with the action GitHub Script Action:

Comment on an issue

on:
  issues:
    types: [opened]

jobs:
  comment:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/github-script@v3
        with:
          github-token: ${{secrets.GITHUB_TOKEN}}
          script: |
            github.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: '👋 Thanks for reporting!'
            })

Apply a label to an issue

on:
  issues:
    types: [opened]

jobs:
  apply-label:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/github-script@v3
        with:
          github-token: ${{secrets.GITHUB_TOKEN}}
          script: |
            github.issues.addLabels({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              labels: ['Triage']
            })

Welcome a first-time contributor

on: pull_request

jobs:
  welcome:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/github-script@v3
        with:
          github-token: ${{secrets.GITHUB_TOKEN}}
          script: |
            // Get a list of all issues created by the PR opener
            // See: https://octokit.github.io/rest.js/#pagination
            const creator = context.payload.sender.login
            const opts = github.issues.listForRepo.endpoint.merge({
              ...context.issue,
              creator,
              state: 'all'
            })
            const issues = await github.paginate(opts)

            for (const issue of issues) {
              if (issue.number === context.issue.number) {
                continue
              }

              if (issue.pull_request) {
                return // Creator is already a contributor.
              }
            }

            await github.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: 'Welcome, new contributor!'
            })

What is the motivation / use case for changing the behavior?

Improve issue management 😊