Integration test framework for MCM

[PadmaB]

Story

As machine-controller-manager developer I want to run a set of integration tests that are easy to validate breaking PRs. This framework must be golang based can be easily expanded to add new tests.

Motivation

Currently, we have a bash based integration tests (IT) here. We would like to have completely refined integration tests for MCM using Golang tests.

The idea would be to have a robust test environment, automates machine/machineSet/machineDeployment creation/deletion and such operations making it is easy for developers to run their tests in an integrated environment, publishing the results.

Acceptance Criteria

• A Golang Framework to accommodate a robust set of integration tests that can be easily adapted.
• Ensure the end-to-end automation
• Validate the results
• Integrate the existing tests into TestMachinery. Refer - gardener extension GCP, etcd backup restore tests

Definition of Done

• Knowledge is distributed: Have you spread your knowledge in pair programming/code review?
• Integration tests are provided: Have you written automated integration tests?
• Minimum API exposure: If you have added/changed public API, was it really necessary/is it minimal?
• Operations guide: Have you updated the operations guide about ops-relevant changes?
• User documentation: Have you updated the READMEs/docs/how-tos about user-relevant changes?

[prashanth26]

Adopt the test framework to the out of tree code style.