CDRIVER-4333 unskip `mongohouse` tests (#1518)

* remove `mongohouse` tests from skip

* do not run `drop` in mongohouse tests

* do not run `configureFailPoint` in mongohouse tests

* fix leak

* pass `ON` for `RUN_MONGOHOUSE_TESTS`

To enable using `test_framework_getenv_bool`. "true" is not a supported value.

* add helper `test_framework_is_mongohouse`

To reduce hard coding of the string "RUN_MONGOHOUSE_TESTS"