When starting elastic-agent with a configuration file that enables shipper, but the agent fails to resolve the elastic-agent-shipper component, should fail instead of falling back to Filebeat.

The reason behind this was that when I tried to use the agent with the shipper and I had not previously set up a configured agent to include shipper, it fall back to filebeat giving me the wrong assumption that initially, it worked.
I found that there was a problem with the packaging after doing some investigation as to why I was not seeing the results I was expecting.

Originally reported by @alexsapran