Update pyScss to 1.3.7

pyScss 1.3.4 is not compatible with setuptools 46.
pyScss 1.3.7 was releaed to make it work with setuptools 46.

Note that a workaround for the material design theme
in commit ddc52a7405 is not backported
in this change as the workaround is a partial fix of bug 1771559.
Instead, a release note to mention this as a known issue is added.

python-memcached in test-requirements.txt is updated to
pass the requirements-check job.

Depends-On: https://review.opendev.org/716004
Change-Id: I336a3449c1ed8be3984da6366e9b45f8e4d3f5c0
(cherry picked from commit 2c44702724)

lower-constraints.txt

@@ -92,7 +92,7 @@ pymongo==3.0.2
 pyOpenSSL==17.1.0
 pyparsing==2.1.0
 pyperclip==1.5.27
-pyScss==1.3.4
+pyScss==1.3.7
 python-cinderclient==4.0.1
 python-dateutil==2.5.3
 python-glanceclient==2.8.0

releasenotes/notes/pyscss-and-setuptools-7634dcee9d62bde9.yaml

@@ -0,0 +1,13 @@
+---
+issues:
+  - |
+    The material design theme is now broken with pyScss 1.3.7
+    (also see the upgrade notice section).
+    If you really depends on the material design theme, keep using
+    pyScss 1.3.4 with setuptools<45 (while the horizon dependencies list
+    says pyScss>=1.3.7 is required).
+    The issue is tracked via [:bug:`1771559`].
+upgrade:
+  - |
+    pyScss 1.3.7 is now required due to the incompatibility that
+    pyScss 1.3.4 used before in horizon does not work with setuptools 46.

requirements.txt

@@ -30,7 +30,7 @@ oslo.utils>=3.33.0 # Apache-2.0
 osprofiler>=2.3.0 # Apache-2.0
 Pint>=0.5 # BSD
 pymongo!=3.1,>=3.0.2 # Apache-2.0
-pyScss!=1.3.5,>=1.3.4 # MIT License
+pyScss>=1.3.7 # MIT License
 python-cinderclient>=4.0.1 # Apache-2.0
 python-glanceclient>=2.8.0 # Apache-2.0
 python-keystoneclient>=3.15.0 # Apache-2.0

test-requirements.txt

@@ -17,7 +17,8 @@ flake8-import-order==0.12 # LGPLv3
 mock>=2.0.0 # BSD
 mox3>=0.20.0 # Apache-2.0
 nodeenv>=0.9.4 # BSD
-python-memcached>=1.59 # PSF
+python-memcached>=1.59;python_version=='2.7' # PSF
+python-memcached>=1.59;python_version>='3.4' # PSF
 pylint==2.2.2;python_version>='3.0' # GPLv2
 selenium>=2.50.1 # Apache-2.0
 testscenarios>=0.4 # Apache-2.0/BSD