Save a reference to created async tasks, to avoid tasks potentially disappearing (redis#2816)

* save a reference to created tasks, to avoid tasks disappearing mid-execution * Ignore linter * Ignore linter --------- Co-authored-by: dvora-h <67596500+dvora-h@users.noreply.github.com>

Author: anio

redis/asyncio/cluster.py

@@ -1135,13 +1135,13 @@ def set_nodes(
  if remove_old:
  for name in list(old.keys()):
  if name not in new:
- asyncio.create_task(old.pop(name).disconnect())
+ task = asyncio.create_task(old.pop(name).disconnect()) # noqa
 
  for name, node in new.items():
  if name in old:
  if old[name] is node:
  continue
- asyncio.create_task(old[name].disconnect())
+ task = asyncio.create_task(old[name].disconnect()) # noqa
  old[name] = node
 
  def _update_moved_slots(self) -> None: