Fix compatibility with Celery 5.2

celery_haystack/__init__.py

-__version__ = '0.20.post2'
+__version__ = '0.21'
 
 
 def version_hook(config):

celery_haystack/tasks.py

@@ -160,5 +160,5 @@ class CeleryHaystackUpdateIndex(current_app.Task):
         logger.info("Finishing update index")
 
 
-current_app.tasks.register(CeleryHaystackSignalHandler)
-current_app.tasks.register(CeleryHaystackUpdateIndex)
+CeleryHaystackSignalHandler = current_app.register_task(CeleryHaystackSignalHandler())
+CeleryHaystackUpdateIndex = current_app.register_task(CeleryHaystackUpdateIndex())

docs/changelog.rst

 Changelog
 =========
 
+v0.21 (2021-12-25)
+------------------
+
+* Added support for Celery 5.2
+
 v0.20 (2021-02-11)
 ------------------