gitea workflow: start switching from using Makefile to direkt commands

.gitea/workflows/nightly_test.yml

@@ -4,12 +4,12 @@ on:
     - cron: "05 05 * * *"
 
 jobs:
-  make-test:
-    name: Run make test
+  run-tests:
+    name: Execute tox to run the test suite
     runs-on: [django-dav-events]
     steps:
       - name: "Checkout the repository"
         run: git clone "${{ gitea.server_url }}/${{ gitea.repository }}" ./repository
-      - name: "Run make test"
+      - name: "Run test via tox"
         working-directory: ./repository
-        run: make test
+        run: tox

.gitea/workflows/test_on_push.yml

@@ -2,12 +2,12 @@ name: Run tests
 on: [push]
 
 jobs:
-  make-test:
-    name: Run make test
+  run-tests:
+    name: Execute tox to run the test suite
     runs-on: [django-dav-events]
     steps:
       - name: "Checkout the repository"
         run: git clone "${{ gitea.server_url }}/${{ gitea.repository }}" ./repository
-      - name: "Run make test"
+      - name: "Run tests via tox"
         working-directory: ./repository
-        run: make test
+        run: tox