Use full property name in error message.

Author: joshiste

spring-boot-admin-client/src/main/java/de/codecentric/boot/admin/client/registration/DefaultApplicationFactory.java

@@ -95,7 +95,7 @@ protected String getServiceBaseUrl() {
  }
 
  if (getLocalServerPort() == null) {
- throw new IllegalStateException("couldn't determine local port. Please supply service-base-url.");
+ throw new IllegalStateException("couldn't determine local port. Please set spring.boot.admin.client.instance.service-base-url.");
  }
 
  return UriComponentsBuilder.newInstance()