Fix ./jstests/replsets/initial_sync_oplog_hole.js to prevent using stale heartbeat info in the test.

_waitForIndicator function in ./src/mongo/shell/replsettest.js always executes the "replSetGetStatus" cmd on primary and gets the member node's state. If the primary is not holding up-to-date info about the replica set members, then replTest.waitForState can work incorrectly and lead to failures like in BF-11225.

Fix is to use rslib's waitForState which verifies the node's state by making a call directly to that node in question.