EHN: add wait-for-it to linkahead start-up

linkahead/.gitignore

 cert
+doip-linkahead.json

linkahead/Makefile

 
-start: doip-linkahead.json cert
+start: cert doip-linkahead.json
 	@echo "Start LinkAhead"
 	docker compose up --build --detach
+	docker exec linkahead-doip-server-1 /opt/caosdb/git/caosdb-advanced-user-tools/.docker/wait-for-it.sh localhost:10443 -t 500 -- echo "LINKAHEAD ONLINE"
 
 doip-linkahead.json: doip-linkahead.template.json cert/pubkey.pem .env
 	sed "s:PUBKEY:$$(sed "/-----/d" cert/pubkey.pem | tr -d '\n\t\r'):" $< > $@