Switch to docker buildbot

Author: colinmcneil

.github/workflows/extension.yml

@@ -21,8 +21,8 @@ jobs:
       - name: Login to Docker Hub
         uses: docker/login-action@v3
         with:
-          username: dockerpublicbot
-          password: ${{ secrets.DOCKERPUBLICBOT_WRITE_PAT }}
+          username: dockerbuildbot
+          password: ${{ secrets.DOCKERBUILDBOT_WRITE_PAT }}
 
       - name: Build and push
         uses: docker/build-push-action@v5