Remove dead code since args are always present on fields and directives

Replicates graphql/graphql-js@1512eeb

Author: Cito

graphql/type/directives.py

@@ -1,4 +1,4 @@
-from typing import Any, Dict, Sequence, cast
+from typing import Any, Dict, Optional, Sequence, cast
 
 from ..language import ast, DirectiveLocation
 from ..pyutils import inspect, FrozenList
@@ -26,6 +26,12 @@ class GraphQLDirective:
     Type system creators will usually not create these directly.
     """
 
+    name: str
+    locations: Sequence[DirectiveLocation]
+    args: Dict[str, GraphQLArgument]
+    description: Optional[str]
+    ast_node: Optional[ast.DirectiveDefinitionNode]
+
     def __init__(
         self,
         name: str,

graphql/type/introspection.py

@@ -95,7 +95,7 @@
         ),
         "args": GraphQLField(
             GraphQLNonNull(GraphQLList(GraphQLNonNull(__InputValue))),
-            resolve=lambda directive, _info: (directive.args or {}).items(),
+            resolve=lambda directive, _info: directive.args.items(),
         ),
     },
 )
@@ -323,7 +323,7 @@ def of_type(type_, _info):
         ),
         "args": GraphQLField(
             GraphQLNonNull(GraphQLList(GraphQLNonNull(__InputValue))),
-            resolve=lambda item, _info: (item[1].args or {}).items(),
+            resolve=lambda item, _info: item[1].args.items(),
         ),
         "type": GraphQLField(
             GraphQLNonNull(__Type), resolve=lambda item, _info: item[1].type