Add the matrix strategy to workflow to make integration tests faster

[maxday]

What does this PR do?

This PR makes the integration testing step faster by using the matrix strategy, it will run tests in parallel.

Motivation

Increase productivity by reducing waiting time

Testing Guidelines

Codebase was not change but a refactoring for integration testing has been made. This should not break the integration tests and should be fully backward compatible

Additional Notes

Current average workflow time for the integration tests step : around 10min With this PR, the new time is about 6min

Types of changes

• [ ] Bug fix
• [ ] New feature
• [ ] Breaking change
• [x] Misc (docs, refactoring, dependency upgrade, etc.)

Check all that apply

• [x] This PR's description is comprehensive
• [ ] This PR contains breaking changes that are documented in the description
• [ ] This PR introduces new APIs or parameters that are documented and unlikely to change in the foreseeable future
• [ ] This PR impacts documentation, and it has been updated (or a ticket has been logged)
• [ ] This PR's changes are covered by the automated tests
• [ ] This PR collects user input/sensitive content into Datadog