Align operation name of MP rest client spans with server-side JAX-RS

[pavolloffay]

At the moment the operation name of rest client spans are HTTP verbs. However in the client filter we have access to the Method (org.eclipse.microprofile.rest.client.invokedMethod) which is being invoked so we have access to path annotation and also FQCN. Based on this data we can use the same operation names as on server side:

• class-method - the provider for the default operation name.
• http-path - the operation name has the following form <HTTP method>:<@Path value of endpoint’s class>/<@Path value of endpoint’s method>. For example if the class is annotated with @Path("service") and method @Path("endpoint/{id: \\d+}") then the operation name is GET:/service/endpoint/{id: \\d+}.

[pavolloffay]

@fmhwong promised to implement this one.