Add custom encode/decode callback tests for refresh tokens

Author: vimalloc

tests/test_decode_tokens.py

@@ -151,6 +151,10 @@ def get_encode_key_1(identity):
         with app.test_request_context():
             token = create_access_token('username')
             decode_token(token)
+    with pytest.raises(InvalidSignatureError):
+        with app.test_request_context():
+            token = create_refresh_token('username')
+            decode_token(token)
 
     @jwtM.decode_key_loader
     def get_decode_key_1(claims):
@@ -160,3 +164,5 @@ def get_decode_key_1(claims):
     with app.test_request_context():
         token = create_access_token('username')
         decode_token(token)
+        token = create_refresh_token('username')
+        decode_token(token)