Add missing collect_by_mro to typing stubs

Fixes #711

changelog.d/711.change.rst

@@ -0,0 +1 @@
+The type stubs for ``attr.s()`` and ``attr.make_class()`` are not missing the *collect_by_mro* argument anymore.

src/attr/__init__.pyi

@@ -273,6 +273,7 @@ def attrs(
     eq: Optional[bool] = ...,
     order: Optional[bool] = ...,
     auto_detect: bool = ...,
+    collect_by_mro = ...,
     getstate_setstate: Optional[bool] = ...,
     on_setattr: Optional[_OnSetAttrArgType] = ...,
     field_transformer: Optional[_FieldTransformer] = ...,
@@ -297,6 +298,7 @@ def attrs(
     eq: Optional[bool] = ...,
     order: Optional[bool] = ...,
     auto_detect: bool = ...,
+    collect_by_mro = ...,
     getstate_setstate: Optional[bool] = ...,
     on_setattr: Optional[_OnSetAttrArgType] = ...,
     field_transformer: Optional[_FieldTransformer] = ...,
@@ -386,6 +388,7 @@ def make_class(
     auto_exc: bool = ...,
     eq: Optional[bool] = ...,
     order: Optional[bool] = ...,
+    collect_by_mro = ...,
     on_setattr: Optional[_OnSetAttrArgType] = ...,
     field_transformer: Optional[_FieldTransformer] = ...,
 ) -> type: ...

tests/typing_example.py

@@ -244,3 +244,8 @@ class NGFrozen:
 
 # XXX: needs support in mypy
 # ngf = NGFrozen(1)
+
+
+@attr.s(collect_by_mro=True)
+class MRO:
+    pass