Migrate from vanilla go tests to Ginkgo

[vprashar2929]

Since new operator-sdk version's make use of Ginkgo for writing the tests maybe we can also migrate from existing vanilla go tests for testing Operator towards Gimkgo

[vprashar2929]

Other forms for tests than ginkgo are also available here: https://sdk.operatorframework.io/docs/building-operators/golang/testing/#e2e-integration-tests