maint: revert dropping support for py36

For reference note that JupyterHub 3 and 4 requires python 3.7, so
batchspawner of a modern version on python 3.6 will probably use
JupyterHub 1 or 2.

Author: consideRatio

.github/workflows/test.yaml

@@ -23,20 +23,23 @@ on:
 jobs:
   pytest:
     name: Run pytest
-    runs-on: ubuntu-22.04
+    runs-on: ${{ matrix.runs-on || 'ubuntu-22.04' }}
 
     strategy:
       fail-fast: false
       matrix:
         include:
           # test oldest supported version
-          - python-version: "3.7"
+          - python-version: "3.6"
             pip-install-spec: "jupyterhub==1.5.1 sqlalchemy==1.*"
+            runs-on: ubuntu-20.04 # python 3.6 is only available in 20.04
 
-          - python-version: "3.8"
+          - python-version: "3.7"
             pip-install-spec: "jupyterhub==2.* sqlalchemy==1.*"
-          - python-version: "3.10"
+          - python-version: "3.8"
             pip-install-spec: "jupyterhub==3.*"
+          - python-version: "3.10"
+            pip-install-spec: "jupyterhub==4.*"
           - python-version: "3.11"
             pip-install-spec: "jupyterhub==4.*"
 

pyproject.toml

@@ -28,6 +28,7 @@ profile = "black"
 #
 [tool.black]
 target_version = [
+    "py36",
     "py37",
     "py38",
     "py39",

setup.py

@@ -33,7 +33,7 @@
         "About Jupyterhub": "http://jupyterhub.readthedocs.io/en/latest/",
         "Jupyter Project": "http://jupyter.org",
     },
-    python_requires=">=3.7",
+    python_requires=">=3.6",
     install_require={
         "jinja2",
         "jupyterhub>=1.5.1",