on PRs, build image but do not push (#332)

.github/workflows/build-only.yml

@@ -1,9 +1,9 @@
-# Builds any changed docker images and pushes to Dockerhub
-# Only runs for PRs; does not re-deploy
+# Builds any changed docker images
+# Only runs for PRs; does not push to Dockerhub or re-deploy
 #
 # The bulk of this workflow happens in the deploy.py script
 
-name: Build, push Docker image
+name: Build Docker image
 
 on:
   pull_request:
@@ -14,15 +14,14 @@ on:
 
 env:
   PYTHON_VERSION: 3.8
-  DOCKERHUB_USERNAME: earthlabcu
   GKE_PROJECT: ea-jupyter
   GKE_ZONE: us-central1-b
   GKE_CLUSTER: jhub2
 
 
 jobs:
 
-  build-push:
+  build-image:
     runs-on: ubuntu-latest
 
     strategy:
@@ -38,11 +37,5 @@ jobs:
         with:
           python-version: ${{ env.PYTHON_VERSION }}
 
-      - name: Login to Docker Hub
-        uses: docker/login-action@v1
-        with:
-          username: ${{ env.DOCKERHUB_USERNAME }}
-          password: ${{ secrets.DOCKERHUB_TOKEN }}
-
       - name: Build the Docker image
-        run: python deploy.py --build --push ${{matrix.hubname}}
+        run: python deploy.py --build ${{matrix.hubname}}