Several on_shutdown test enhancements

• test: fix on_shutdown test log parsing
• test: refactor gl119_panic_on_shutdown
• test: single out shutdown tests

test/int/test_couple.py

 import funcy  # type: ignore
 import pytest
 from conftest import Cluster, Instance
-from time import sleep
 
 
 @funcy.retry(tries=20, timeout=0.1)
@@ -120,47 +119,3 @@ def test_restart_both(cluster2: Cluster):
     i1.raft_propose_eval("rawset(_G, 'check', true)")
     assert i1.eval("return check") is True
     assert i2.eval("return check") is True
-
-
-def test_gl119_panic_in_on_shutdown(cluster2: Cluster):
-    i1, i2 = cluster2.instances
-
-    i2.call("picolib.raft_timeout_now", timeout=0.01)
-    assert i2.terminate() == 0
-
-    # second instance terminates first, so it becomes a follower
-    i2.terminate()
-    # terminate the leader, so the follower can't acquire the read barrier
-    i1.terminate()
-
-    i2.start()
-    # wait for the follower to start acquiring the read barrier
-    sleep(1)
-    assert i2.terminate() == 0
-
-
-# it's 2022 and i have to work around a mypy bug reported in 2018
-on_shutdown_timed_out: bool
-
-
-def test_gl127_graceul_shutdown(cluster2: Cluster):
-    i1, i2 = cluster2.instances
-
-    # make sure i1 is leader
-    i1.promote_or_fail()
-    i2.wait_online()
-
-    global on_shutdown_timed_out
-    on_shutdown_timed_out = False
-
-    def check_log_line(log):
-        if "on_shutdown triggers are timed out" in log:
-            global on_shutdown_timed_out
-            on_shutdown_timed_out = True
-
-    i1.on_output_line(check_log_line)
-    # on_shutdown triggers will timeout after 3sec
-    # so we must wait longer than # that
-    i1.terminate(kill_after_seconds=10)
-
-    assert not on_shutdown_timed_out