Transfer to GitHub action

[peter279k]

As title, since Travis CI will not be friendly for open source projects, I think it's time to transfer to the GitHub action.

[me-shaon]

@nahid I've added github workflow for this package, but the tests will fail due to old dependencies. The issue is not with the workflow but the package dependencies. Please check the workflow logs.
https://github.com/nahid/qarray/actions/runs/1595262009

You need to decide whether you should support old versions. Otherwise it'd be hard to fix the tests.

[nahid]

@me-shaon it'll be complicated if we support the legacy PHP versions. So I think we should remove old PHP versions support from this package and PHP 7.1 should be minimum version.

[peter279k]

It's related to issue #6.

I think there're two approaches to fix installing dependencies issue:

• In order to support lower PHP versions, using the "myclabs/deep-copy": "^1.7", on Composer.json.
• In order to support PHP 7.1 version at least, using the "myclabs/deep-copy": "^1.8", on Composer.json. And it should let this package require php-7.1 version at least.