Add tests for JSONDecodeError attrs

Author: jceresini

stubs/requests/@tests/test_cases/check_jsondecodeerror.py

@@ -0,0 +1,7 @@
+import requests
+from requests.exceptions import JSONDecodeError
+
+try:
+    requests.get("https://httpbin.org/html")
+except JSONDecodeError as exc:
+    print(f"Error. doc: {exc.doc}, msg: {exc.msg}, pos: {exc.pos}")