Adding unit test for ephemeral feature flag

This was something that was missing in #707.
Adding a new test to make sure the ephemeral feature flag from upstream
is set up correctly by the script.

test/entrypoint/should_switch_to_ephemeral_upstream_feature/runsvc.sh

@@ -0,0 +1,31 @@
+#!/bin/bash
+
+set -euo pipefail
+
+export LIGHTGREEN='\e[0;32m'
+export LIGHTRED='\e[0;31m'
+export WHITE='\e[0;97m'
+export RESET='\e[0m'
+
+log(){
+  printf "\t${WHITE}$@${RESET}\n" 2>&1
+}
+
+success(){
+  printf "\t${LIGHTGREEN}$@${RESET}\n" 2>&1
+}
+
+error(){
+  printf "\t${LIGHTRED}$@${RESET}\n" 2>&1
+  exit 1
+}
+
+success ""
+success "Running the service..."
+# test if --once is present as a parameter
+echo "$*" | grep -q 'once' && error "Should not include --once in the parameters"
+success "...successful"
+touch runsvc_ran
+success ""
+
+