ci: add example-services submodule check to justfile init

Author: shree-iyengar-dls

justfile

@@ -3,8 +3,12 @@ RUNNER := `command -v docker || command -v podman`
 
 default: compose serve
 
-init:
-    git submodule update --init --recursive
+init-example-services:
+    #!/usr/bin/env bash
+    # Clone the example-services submodule if needed but leave it alone otherwise
+    if [[ $(git submodule status example-services) =~ ^- ]]; then
+        git submodule update --init example-services
+    fi
 
 compose +ARGS="up -d --no-recreate": init
     {{ RUNNER }} compose -f tests/system_tests/compose.yaml {{ARGS}}