Bump botorch version to 0.8.5 (#1608)

Summary:
Pull Request resolved: #1608

As titled

Reviewed By: saitcakmak

Differential Revision: D45665503

fbshipit-source-id: aaf3cad9fee6c16db44f32df5a48978720594b62

Author: mpolson64

setup.py

@@ -9,7 +9,7 @@
 from setuptools import find_packages, setup
 
 # TODO: read pinned Botorch version from a shared source
-PINNED_BOTORCH_VERSION = "0.8.4"
+PINNED_BOTORCH_VERSION = "0.8.5"
 
 if os.environ.get("ALLOW_BOTORCH_LATEST"):
     # allows a more recent previously installed version of botorch to remain