Merge bitcoin/bitcoin#30559: test: Try previously intermittently broken USDT test again

fa2269d test: Try previously intermittently broken USDT test again (MarcoFalke)

Pull request description:

  Seems fine to try it again, given that the infra changed in the meantime.

  Should be trivial to disable again, on the first failure.

  Ref: bitcoin/bitcoin#27380 (comment)

ACKs for top commit:
  fanquake:
    ACK fa2269d - seems fine to re-try this now.

Tree-SHA512: e203625b49019517def8e92cc465dd947d5aa85a080d370aabce7a45442efc3900b5c3783f6cc15720f81e5aaa3ff193a26be3d33048f20a73cd7b1fce320118

Author: fanquake

test/functional/interface_usdt_mempool.py

@@ -296,10 +296,7 @@ def handle_rejected_event(_, data, __):
         assert_equal(1, len(events))
         event = events[0]
         assert_equal(bytes(event.hash)[::-1].hex(), tx["tx"].hash)
-        # The next test is already known to fail, so disable it to avoid
-        # wasting CPU time and developer time. See
-        # https://github.com/bitcoin/bitcoin/issues/27380
-        #assert_equal(event.reason.decode("UTF-8"), "min relay fee not met")
+        assert_equal(event.reason.decode("UTF-8"), "min relay fee not met")
 
         bpf.cleanup()
         self.generate(self.wallet, 1)