Fix duplicate logging to Healthchecks and send "after_*" hooks output to Healthchecks (#328).

tests/integration/hooks/test_healthchecks.py

@@ -0,0 +1,24 @@
+import logging
+
+from flexmock import flexmock
+
+from borgmatic.hooks import healthchecks as module
+
+
+def test_destroy_monitor_removes_healthchecks_handler():
+    logger = logging.getLogger()
+    original_handlers = list(logger.handlers)
+    logger.addHandler(module.Forgetful_buffering_handler(byte_capacity=100, log_level=1))
+
+    module.destroy_monitor(flexmock(), flexmock(), flexmock(), flexmock())
+
+    assert logger.handlers == original_handlers
+
+
+def test_destroy_monitor_without_healthchecks_handler_does_not_raise():
+    logger = logging.getLogger()
+    original_handlers = list(logger.handlers)
+
+    module.destroy_monitor(flexmock(), flexmock(), flexmock(), flexmock())
+
+    assert logger.handlers == original_handlers