Drop support for Python 3.5 (PyGithub#1770)

In preperation for starting to use 3.6+ only features, stop testing
Python 3.5 in our CI, and bump our minimum required version.

Author: s-t-e-v-e-n-k

.github/workflows/ci.yml

@@ -9,7 +9,7 @@ jobs:
     name: test (Python ${{ matrix.python-version }})
     strategy:
       matrix:
-        python-version: [3.5, 3.6, 3.7, 3.8, 3.9]
+        python-version: [3.6, 3.7, 3.8, 3.9]
     steps:
       - uses: actions/checkout@v2
       - name: Set up Python

setup.py

@@ -92,14 +92,13 @@
             "Operating System :: OS Independent",
             "Programming Language :: Python",
             "Programming Language :: Python :: 3",
-            "Programming Language :: Python :: 3.5",
             "Programming Language :: Python :: 3.6",
             "Programming Language :: Python :: 3.7",
             "Programming Language :: Python :: 3.8",
             "Programming Language :: Python :: 3.9",
             "Topic :: Software Development",
         ],
-        python_requires=">=3.5",
+        python_requires=">=3.6",
         install_requires=["deprecated", "pyjwt", "requests>=2.14.0"],
         extras_require={"integrations": ["cryptography"]},
         tests_require=["cryptography", "httpretty>=1.0.3"],

tox.ini

@@ -1,12 +1,11 @@
 [tox]
 envlist =
     lint,
-    py{35,36,37,38,39},
+    py{36,37,38,39},
     docs
 
 [gh-actions]
 python =
-    3.5: py35
     3.6: py36, docs, lint
     3.7: py37
     3.8: py38