Kafka franz returns ready OK even when it can't connect

[pedrovsg]

Example code

input: kafka_franz: seed_brokers: [ "localhost:6666" ] topics: [ "foobar" ] consumer_group: "benthos" ready endpoint returns OK

App dies with sigterm after a few secods

[mihaitodor]

Steps to reproduce:

• Run Benthos with this config:

input:
  kafka_franz:
    seed_brokers: [ "localhost:6666" ]
    topics: [ "foobar" ]
    consumer_group: "benthos"

• Run curl -v http://localhost:4195/ready and you'll get status 200.