Add RawJSON to simplejson stubs (#5921)

Update METADATA.toml version

stubs/simplejson/METADATA.toml

@@ -1,2 +1,2 @@
-version = "0.1"
+version = "3.17"
 python2 = true

stubs/simplejson/simplejson/__init__.pyi

@@ -2,6 +2,7 @@ from typing import IO, Any, Text, Union
 
 from simplejson.decoder import JSONDecoder as JSONDecoder
 from simplejson.encoder import JSONEncoder as JSONEncoder, JSONEncoderForHTML as JSONEncoderForHTML
+from simplejson.raw_json import RawJSON as RawJSON
 from simplejson.scanner import JSONDecodeError as JSONDecodeError
 
 _LoadsString = Union[Text, bytes, bytearray]

stubs/simplejson/simplejson/raw_json.pyi

@@ -0,0 +1,3 @@
+class RawJSON(object):
+    encoded_json: str
+    def __init__(self, encoded_json: str) -> None: ...