Cleanup, add more Async ENS tests, test performance improvements

* Add some missing awaits
* Add a lot more testing around AsyncENS. We can think about splitting AsyncEthereumTesterProvider tests off into their own CI job if they get too big but we should provide ample testing around the async implementation to make sure it's all wired up correctly.
* Cleanup for better readability and consistency across ENS and AsyncENS
* Keep async_ens_setup as module scope with a module-scoped event_loop fixture and add a module-scoped async_w3 for ens module

* Fix some minor warnings with optionals where ``None`` is being passed in
* nit: Since we are adding so many new lines, match code style to ideal rest of library for consistency. Trailing commas with new arguments allow for a cleaner git blame / git history since the next bit of code added would only touch the new line that is created, etc. (``black`` formatting PRs are coming in now though so this wasn't very important after the first commit that was squashed here).

Author: fselmo

ens/async_ens.py

@@ -34,9 +34,9 @@
 
 class BaseENS:
     w3: 'Web3' = None
+    ens: Union['Contract', 'AsyncContract'] = None
     _resolver_contract: Union[Type['Contract'], Type['AsyncContract']] = None
     _reverse_resolver_contract: Union[Type['Contract'], Type['AsyncContract']] = None
-    ens: Union['Contract', 'AsyncContract'] = None
 
     @staticmethod
     @wraps(label_to_hash)
@@ -86,8 +86,10 @@ def parent(name: str) -> str:
         return '' if len(labels) == 1 else '.'.join(labels[1:])
 
     def _decode_ensip10_resolve_data(
-        self, contract_call_result: bytes,
-        extended_resolver: Union['Contract', 'AsyncContract'], fn_name: str,
+        self,
+        contract_call_result: bytes,
+        extended_resolver: Union['Contract', 'AsyncContract'],
+        fn_name: str,
     ) -> Any:
         func = extended_resolver.get_function_by_name(fn_name)
         output_types = get_abi_output_types(func.abi)
@@ -96,9 +98,11 @@ def _decode_ensip10_resolve_data(
         # if decoding a single value, return that value - else, return the tuple
         return decoded[0] if len(decoded) == 1 else decoded
 
-    def _type_aware_resolver(self,
-                             address: ChecksumAddress,
-                             func: str) -> Union['Contract', 'AsyncContract']:
+    def _type_aware_resolver(
+        self,
+        address: ChecksumAddress,
+        func: str,
+    ) -> Union['Contract', 'AsyncContract']:
         return (
             self._reverse_resolver_contract(address=address) if func == 'name' else
             self._resolver_contract(address=address)