Do login into docker hub so we could reliably build our docker image

Otherwise, since limiting is done per IP and we do not know where requests
would be coming from to the docker hub, we could get

    #3 [auth] library/python:pull token for registry-1.docker.io
    #3 DONE 0.0s

    #2 [internal] load metadata for docker.io/library/python:3.11-slim
    #2 ERROR: failed to copy: httpReadSeeker: failed open: unexpected status code https://registry-1.docker.io/v2/library/python/manifests/sha256:5501a4fe605abe24de87c2f3d6cf9fd760354416a0cad0296cf284fddcdca9e2: 429 Too Many Requests - Server message: toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit
    ------
     > [internal] load metadata for docker.io/library/python:3.11-slim:
    ------
    django-public.Dockerfile:1
    --------------------
       1 | >>> FROM python:3.11-slim
       2 |     # Install system librarires for Python packages:
       3 |     # * psycopg2
    --------------------
    ERROR: failed to solve: python:3.11-slim: failed to resolve source metadata for docker.io/library/python:3.11-slim: failed to copy: httpReadSeeker: failed open: unexpected status code https://registry-1.docker.io/v2/library/python/manifests/sha256:5501a4fe605abe24de87c2f3d6cf9fd760354416a0cad0296cf284fddcdca9e2: 429 Too Many Requests - Server message: toomanyrequests: You have reached your pull rate limit. You may increase the limit by authenticating and upgrading: https://www.docker.com/increase-rate-limit
    Error: Process completed with exit code 1.

.github/workflows/cli-integration.yml

@@ -19,10 +19,14 @@ jobs:
 
       - name: Build Docker image
         run: |
+          docker login -u "$DOCKER_LOGIN" --password-stdin <<<"$DOCKER_TOKEN"
           docker build \
             -t dandiarchive/dandiarchive-api \
             -f dev/django-public.Dockerfile \
             .
+        env:
+          DOCKER_LOGIN: ${{ secrets.DOCKER_LOGIN }}
+          DOCKER_TOKEN: ${{ secrets.DOCKER_TOKEN }}
 
       - name: Export Docker image
         run: |