Let TypeAlias be a statement (pylint-dev#2250)

Follow-up to fbcff3a.

Author: jacobtylerwalls

astroid/nodes/node_classes.py

@@ -4010,7 +4010,7 @@ def getitem(self, index, context: InferenceContext | None = None):
         return _container_getitem(self, self.elts, index, context=context)
 
 
-class TypeAlias(_base_nodes.AssignTypeNode):
+class TypeAlias(_base_nodes.AssignTypeNode, _base_nodes.Statement):
     """Class representing a :class:`ast.TypeAlias` node.
 
     >>> import astroid

tests/test_type_params.py

@@ -35,6 +35,8 @@ def test_type_alias() -> None:
     assert node.inferred()[0] is node
     assert node.type_params[0].inferred()[0] is node.type_params[0]
 
+    assert node.statement() is node
+
 
 def test_type_param_spec() -> None:
     node = extract_node("type Alias[**P] = Callable[P, int]")