Cleanup: remove unicode prefix, remove explicit inheritance from object (#11015)

* Address UP025: remove unicode literals from strings.

* Address UP004: class inherits from 'object'.

plugins/callback/elastic.py

@@ -138,7 +138,7 @@ class HostData:
         self.finish = time.time()
 
 
-class ElasticSource(object):
+class ElasticSource:
     def __init__(self, display):
         self.ansible_playbook = ""
         self.session = str(uuid.uuid4())