Run Tox tests in the Github Action CI

Also, add some dependencies required to run the tests locally
with Tox. Note that the tests are not passing at the moment,
we will need to update some dependencies and fix other issues.
But this gets us closer to running them, and at least we can
see the progress being made in the CI.

Author: ldionne

.github/workflows/flake8_docs.yaml renamed to .github/workflows/tox.yaml

@@ -1,4 +1,4 @@
-name: Python Flake8, Docs, mypy
+name: Run Tox tests
 
 on:
   - push
@@ -24,3 +24,5 @@ jobs:
       run: tox -e docs
     - name: Tox mypy
       run: tox -e mypy
+    - name: Tox py3
+      run: tox -e py3

tox.ini

@@ -49,6 +49,11 @@ deps =
 commands =
     make -C {toxinidir}/docs/ html
 
+[testenv:py3]
+deps =
+    filecheck
+    lit
+
 [testenv:runserver]
 # Don't use this for production. Just a handy target
 # for local testing.