Declare py38 support

Python 3.8 is one of the new required runtimes for the Victoria release.
Now that we have test coverage for py38 and it is passing, we can add
3.8 as one of the supported runtimes in the project metadata.

Change-Id: I97179030993c0b49ffe93aa28ffc672c6b859439
Signed-off-by: Sean McGinnis <sean.mcginnis@gmail.com>

.zuul.yaml

@@ -1,8 +1,8 @@
 - job:
-    name: shade-tox-py35-tips
-    parent: openstack-tox-py35
+    name: shade-tox-py38-tips
+    parent: openstack-tox-py38
     description: |
-      Run tox python 35 unittests against master of important libs
+      Run tox python 38 unittests against master of important libs
     vars:
       tox_install_siblings: true
       zuul_work_dir: src/opendev.org/openstack/shade
@@ -18,10 +18,10 @@
     name: shade-tox-tips
     check:
       jobs:
-        - shade-tox-py35-tips
+        - shade-tox-py38-tips
     gate:
       jobs:
-        - shade-tox-py35-tips
+        - shade-tox-py38-tips
 
 - job:
     name: shade-functional-devstack-base

setup.cfg

@@ -18,6 +18,7 @@ classifier =
     Programming Language :: Python :: 3
     Programming Language :: Python :: 3.6
     Programming Language :: Python :: 3.7
+    Programming Language :: Python :: 3.8
 
 [entry_points]
 console_scripts =