need to build image on latest Dockerfile before running tests

.github/workflows/tests.yml

@@ -1,16 +1,36 @@
 name: Run deenurp tests on deenurp image
 
-on:
-  push:
-    branches: [ master ]
-  pull_request:
-    branches: [ master ]
+on: push
 
 jobs:
-  build:
+  push_to_registry:
+    environment: docker_build
+    runs-on: ubuntu-latest
+    steps:
+      -
+        name: Set env
+        run: echo "sha_short=$(git rev-parse --short HEAD)" >> $GITHUB_ENV
+      -
+        name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+      -
+        name: Login to GitHub Container Registry
+        uses: docker/login-action@v1
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+      -
+        name: Build and push
+        uses: docker/build-push-action@v2
+        with:
+          push: true
+          tags: |
+            ghcr.io/fhcrc/deenurp:${{ env.sha_short }}  
+  test:
     runs-on: ubuntu-latest
     container:
-      image: ghcr.io/fhcrc/deenurp:latest
+      image: ghcr.io/fhcrc/deenurp:${{ env.sha_short }}
     steps:
     - uses: actions/checkout@v3
     - run: |