Port the parser benchmark

Author: ktosiek

tests/benchmarks/test_parser.py

@@ -0,0 +1,9 @@
+from graphql import parse, DocumentNode
+
+# noinspection PyUnresolvedReferences
+from ..fixtures import kitchen_sink_query  # noqa: F401
+
+
+def test_parsing_kitchen_sink_query(benchmark, kitchen_sink_query):  # noqa: F811
+    query = benchmark(lambda: parse(kitchen_sink_query))
+    assert isinstance(query, DocumentNode)