Update os-brick library to 2.8.6

The previous version contained a regression that affected operation
when running under Python 2.7 while using the Dell EMC VxFlex OS
(ScaleIO) storage backend.

Change-Id: I018007bd865b69631c21af83efdf6aba981161f1

lower-constraints.txt

@@ -64,7 +64,7 @@ networkx==1.11
 oauth2client==1.5.0
 openstackdocstheme==1.20.0
 os-api-ref==1.4.0
-os-brick==2.8.5
+os-brick==2.8.6
 os-client-config==1.29.0
 os-win==3.0.0
 oslo.cache==1.29.0

releasenotes/notes/ossn-0086-followup-f82a0efa264f68d6.yaml

@@ -0,0 +1,11 @@
+---
+upgrade:
+  - |
+    This release updates the os-brick library used by Cinder to version
+    2.8.6 to correct a problem with the fix for `Bug #1823200
+    <https://bugs.launchpad.net/cinder/+bug/1823200>`_ in the previous
+    os-brick release.  It does not contain any Cinder code changes.
+
+    See the `os-brick 2.8.6 release notes
+    <https://docs.openstack.org/releasenotes/os-brick/stein.html#relnotes-2-8-6-stable-stein>`_
+    for more information.

requirements.txt

@@ -58,7 +58,7 @@ suds-jurko>=0.6 # LGPLv3+
 WebOb>=1.7.1 # MIT
 oslo.i18n>=3.15.3 # Apache-2.0
 oslo.vmware>=2.17.0 # Apache-2.0
-os-brick>=2.8.5 # Apache-2.0
+os-brick>=2.8.6 # Apache-2.0
 os-win>=3.0.0 # Apache-2.0
 tooz>=1.58.0 # Apache-2.0
 google-api-python-client>=1.4.2 # Apache-2.0