USe new tox and update githubworkflows

This patch updates tox to the latest and updates the github workflows
to use tox-gh, which is claimed to work with github parallel tox runs

.github/workflows/master-build.yml

@@ -27,7 +27,7 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install tox tox-gh-actions
+        pip install tox tox-gh>=1.2
     - name: Test with tox
       run: tox
 

.github/workflows/python.yml

@@ -17,6 +17,6 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
-        pip install tox tox-gh-actions
+        pip install tox tox-gh>=1.2
     - name: Test with tox
       run: tox