release-test.yml: also fetch host key from grenoble

.github/workflows/release-test.yml

@@ -73,11 +73,11 @@ jobs:
         ssh-private-key: ${{ secrets.IOTLAB_PRIVATE_KEY }}
     - name: Fetch host keys from IoT-LAB sites
       if: ${{ matrix.pytest_mark == 'iotlab_creds' }}
-      # lille is not being used in the most recent release specs but kept in for
+      # lille and saclay are not being used in the most recent release specs but kept in for
       # backwords compatibility
       run: |
         IOTLAB_USER=$(cat ~/.iotlabrc | cut -f1 -d:)
-        for site in saclay lille strasbourg; do
+        for site in grenoble saclay lille strasbourg; do
           ssh -oStrictHostKeyChecking=accept-new \
             "${IOTLAB_USER}@${site}.iot-lab.info exit"
         done