Voapi 574 acceptance tests

[jcorrea-splunk]

@kevalds51 Please review when possible.

[kevalds51]

Here is what I did:-

• Moved the paging-policy test, escalation-policy test and the VO_ROTATION_GROUP_SLUG env variables required by it to another branch called add-remaining-acceptance-tests for WIP tests.
• Removed the TF_ACC env variable by using the -short flag feature in go test. Hence, when the user runs make test it will only run the unit test. Acceptance tests will only run with make testacc
• Updated a couple of test functions to indicate that they are acceptance tests.
• Clean-up and fixed a test in provider_test.go

Everything else looks pretty good to me! 💯