Change integration tests under DBInstallBase to CheckIn tests

After HIVE-18588, some tests including those under DBInstallBase class have been marked as integration tests mainly to keep the test duration low.

Nowadays, Hive developers rarely run all tests locally so separating between integration tests and unit tests does not provide a clear benefit. The separation adds maintenance cost and makes their execution more difficult scaring people away.

The goal of this issue is to change the tests under DBInstallBase from "integration" tests back to regular unit tests and run them as part of the standard maven test phase without any fancy arguments.