GitHub Actions deprecated node12

[fulf]

GitHub Actions workflow currently gives the following warning:

• Node.js 16 actions are deprecated. Please update the following actions to use Node.js 20: actions/checkout@v2, coverallsapp/github-action@master. For more information see: https://github.blog/changelog/2023-09-22-github-actions-transitioning-from-node-16-to-node-20/.
• The following actions uses node12 which is deprecated and will be forced to run on node16: actions/checkout@v2. For more info: https://github.blog/changelog/2023-06-13-github-actions-all-actions-will-run-on-node16-instead-of-node12-by-default/

Solutions:

• update actions/checkout@v2 to actions/checkout@v4
• update coverallsapp/github-action@master to coverallsapp/github-action@v2

[sds]

Thanks for the update!