Add workflow to run evals.

.github/workflows/eval.yml

@@ -0,0 +1,26 @@
+name: eval-workflow
+
+on:
+  push: 
+    # Workflow runs on push to any branch.
+  schedule:
+    - cron: "0 * * * *" # hourly
+
+# TODO(polina-c): add steps that run tests
+
+jobs:
+  eval-job:
+    runs-on: ubuntu-latest
+    environment: eval
+    steps:
+      - name: Check that key is available
+        run: |
+          echo "ENV_KEY has ${#ENV_KEY} characters"
+          echo "REPO_KEY has ${#REPO_KEY} characters"
+
+        env:
+          ENV_KEY: ${{ secrets.ENV_GEMINI_API_KEY }}
+          REPO_KEY: ${{ secrets.REPO_GEMINI_API_KEY }}
+
+
+