Changes import of Hashable to get from collections.abc instead of…

… `collections` (#2067)

wemake_python_styleguide/visitors/ast/builtins.py

@@ -1,7 +1,8 @@
 import ast
 import re
 import string
-from collections import Counter, Hashable, defaultdict
+from collections import Counter, defaultdict
+from collections.abc import Hashable
 from contextlib import suppress
 from typing import (
     ClassVar,