ci: remove support for py36

It is a bit of a bug that 3.6 was still documented as supported, since
synse-server uses asyncio methods which were introduced in py37.

.github/workflows/test.yaml

@@ -8,7 +8,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        py-version: ['3.6', '3.7', '3.8']
+        py-version: ['3.7', '3.8']
     name: Python ${{ matrix.py-version }} Test
     steps:
     - name: Checkout

setup.py

@@ -30,7 +30,7 @@
     license=pkg['__license__'],
     packages=find_packages(exclude=['tests.*', 'tests']),
     include_package_data=True,
-    python_requires='>=3.6',
+    python_requires='>=3.7',
     package_data={
         '': ['LICENSE'],
     },
@@ -57,6 +57,7 @@
         'Natural Language :: English',
         'Programming Language :: Python',
         'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.6',
+        'Programming Language :: Python :: 3.7',
+        'Programming Language :: Python :: 3.8',
     ]
 )

tox.ini

@@ -1,18 +1,16 @@
 [tox]
-envlist = py{36,37,38}
+envlist = py{37,38}
 skip_missing_interpreters = True
 
 
 [gh-actions]
 python =
-    3.6: py36
     3.7: py37
     3.8: py38,lint
 
 
 [testenv]
 basepython =
-    py36: python3.6
     py37: python3.7
     py38: python3.8
 deps =