tests/cg_consistency: changed timeout to 120s

KgoVerifierConsumer uses join timeout of 60 seconds, this may lead to
situation in which consumer group will be rebalancing for 1 minute which
resulted in a test assertion to be triggered. Changed the timeout to
account for the consumer join timeout.

Signed-off-by: Michal Maslanka <michal@redpanda.com>
(cherry picked from commit 08fd7aa)

tests/rptest/tests/consumer_offsets_consistency_test.py

@@ -199,7 +199,7 @@ def fi_worker():
                     )
                     if self.failure_cnt >= 20:
                         break
-                    timeout = 60
+                    timeout = 120
                     if time.time() - self.last_success > timeout:
                         assert False, f"Unable to retrieve group description for {timeout} seconds"
         finally: