PYTHON-5238 - Add async GridFS API docs

Author: NoahStapp

doc/api/gridfs/asynchronous/grid_file.rst

@@ -0,0 +1,19 @@
+:mod:`grid_file` -- Async tools for representing files stored in GridFS
+=======================================================================
+
+.. automodule:: gridfs.asynchronous.grid_file
+   :synopsis: Async tools for representing files stored in GridFS
+
+   .. autoclass:: AsyncGridIn
+      :members:
+
+      .. autoattribute:: _id
+
+   .. autoclass:: AsyncGridOut
+      :members:
+
+      .. autoattribute:: _id
+      .. automethod:: __aiter__
+
+   .. autoclass:: AsyncGridOutCursor
+      :members:

doc/api/gridfs/asynchronous/index.rst

@@ -0,0 +1,18 @@
+:mod:`gridfs async` -- Async tools for working with GridFS
+==========================================================
+
+.. warning:: This API is currently in beta, meaning the classes, methods,
+   and behaviors described within may change before the full release.
+   If you come across any bugs during your use of this API,
+   please file a Jira ticket in the "Python Driver" project at https://jira.mongodb.org/browse/PYTHON.
+
+.. automodule:: gridfs.asynchronous
+   :synopsis: Async tools for working with GridFS
+   :members: AsyncGridFS, AsyncGridFSBucket
+
+Sub-modules:
+
+.. toctree::
+   :maxdepth: 2
+
+   grid_file

doc/api/gridfs/index.rst

@@ -8,7 +8,8 @@
 Sub-modules:
 
 .. toctree::
-   :maxdepth: 2
+   :maxdepth: 3
 
+   asynchronous/index
    errors
    grid_file