fix: acknowledge oversized dropped events (#543)

Author: marandaneto

.sampo/changesets/oversized-event-flush-hang.md

@@ -0,0 +1,5 @@
+---
+pypi/posthog: patch
+---
+
+Prevent flush from hanging after dropping oversized queued events.

posthog/consumer.py

@@ -112,6 +112,7 @@ def next(self):
                     self.log.error(
                         "Item exceeds 900kib limit, dropping. (%s)", str(item)
                     )
+                    queue.task_done()
                     continue
                 items.append(item)
                 total_size += item_size

posthog/test/test_consumer.py

@@ -45,6 +45,7 @@ def test_dropping_oversize_msg(self) -> None:
         next = consumer.next()
         self.assertEqual(next, [])
         self.assertTrue(q.empty())
+        self.assertEqual(q.unfinished_tasks, 0)
 
     def test_upload(self) -> None:
         q = Queue()