Fix typos in test_canvas.py (#8498)

* Fix typos in test_canvas.py

* Fix another typo in test_canvas.py

* Fix another typo in test_canvas.py

* Update t/integration/test_canvas.py

Co-authored-by: Renato Monteiro <45536168+monteiro-renato@users.noreply.github.com>

* Make clearer what a zset is

---------

Co-authored-by: Asif Saif Uddin <auvipy@gmail.com>

t/integration/test_canvas.py

@@ -165,19 +165,19 @@ def test_link_error_callback_retries(self, manager):
     @flaky
     def test_link_error_using_signature_eager(self):
         fail = signature('t.integration.tasks.fail', args=("test",))
-        retrun_exception = signature('t.integration.tasks.return_exception')
+        return_exception = signature('t.integration.tasks.return_exception')
 
-        fail.link_error(retrun_exception)
+        fail.link_error(return_exception)
 
         exception = ExpectedException("Task expected to fail", "test")
         assert (fail.apply().get(timeout=TIMEOUT, propagate=False), True) == (
             exception, True)
 
     def test_link_error_using_signature(self, manager):
         fail = signature('t.integration.tasks.fail', args=("test",))
-        retrun_exception = signature('t.integration.tasks.return_exception')
+        return_exception = signature('t.integration.tasks.return_exception')
 
-        fail.link_error(retrun_exception)
+        fail.link_error(return_exception)
 
         exception = ExpectedException("Task expected to fail", "test")
         assert (fail.delay().get(timeout=TIMEOUT / 10, propagate=False), True) == (
@@ -1877,7 +1877,7 @@ def test_chord_on_error(self, manager):
         backend = fail.app.backend
         j_key = backend.get_key_for_group(original_group_id, '.j')
         redis_connection = get_redis_connection()
-        # The redis key is either a list or zset depending on configuration
+        # The redis key is either a list or a zset (a redis sorted set) depending on configuration
         if manager.app.conf.result_backend_transport_options.get(
             'result_chord_ordered', True
         ):
@@ -3132,12 +3132,12 @@ def task_received_handler(request=None, **kwargs):
                     [
                         stamped_header in link.options
                         for stamped_header in link.options["stamped_headers"]
-                        if link  # the link itself doensn't have a link
+                        if link  # the link itself doesn't have a link
                     ],
                     [
                         stamped_header in link_error.options
                         for stamped_header in link_error.options["stamped_headers"]
-                        if link_error  # the link_error itself doensn't have a link
+                        if link_error  # the link_error itself doesn't have a link_error
                     ],
                 ]
             )