Training improvements after training session 2

[cchet]

FaultTolerance:

• Drawing CircuitBreaker is misunderstood, where is the circuit-breaker defined?

Metrics:

• Add programmatic examples to each Metric-type, where we add tags from data of the request.
  So we can filter the metrics by their tags selectively
• Gauge
  The example shall use an sensor as an example for a gauge to give it more meaning

JWT:

• The OAUTH/OpenID-Connect flow need to be explained
• Drawing is misleading, what is what and why is it there
• JAX-RS-Application example
  We see the smiley when the keycloak is down, but it shouldn't be shown, so we need to handle that.
  Trainees thought that the button click should already be secured, so we need to clarify the example.
• RBAC example
  We need to clarify where to find the token and where to decode it.
• jws_uri -> jwks_uri

General:

• Add redirect from Web-Root-Context to /api/welcome
• Remove dependency "cxf-rt-rs-service-description-openapi-v3". It is only used for openapi-generator but pollutes the whole workspace with many many dependencies.

Infrastructure:

• Binding 0.0.0.0 not working