Update Query constructor syntax

Co-authored-by: Damien Ayers <damien@omad.net>

datacube/api/query.py

@@ -57,7 +57,7 @@ def __init__(self, group_by_func, dimension, units, sort_key=None, group_key=Non
               'source_filter')
 
 
-class Query():
+class Query:
     def __init__(self, index=None, product=None, geopolygon=None, like=None, **search_terms):
         """Parses search terms in preparation for querying the Data Cube Index.