Document JBEAP-13445 fix

This is followup on JBEAP-13445 fix.

Book: development_guide
Section:15.2. Configure Java Authorization Contract for Containers (JACC) Security:

1.

After this fix these commands are not valid anymore:

/subsystem=elytron/policy=jacc:add(jacc-policy=[{name=jacc}])
/subsystem=elytron/policy=policy-provider-a:add(custom-policy=[{name=policy-provider-a, class-name=MyPolicyProviderA, module=x.y.z}])

And shuld be now

/subsystem=elytron/policy=jacc:add(jacc-policy={})
/subsystem=elytron/policy=policy-provider-a:add(custom-policy={class-name=MyPolicyProviderA, module=x.y.z})

2.
As default-policy is now deprecated and ignored, I suggest remove this paragraph:

"The elytron subsystem provides a specific resource definition that can be used to configure a default Java policy provider. The subsystem allows you to define multiple policy providers but select a single one as the default:"

After this fix only one of custom-policy and jacc-policy can be configured. Not both in one moment.

3. default-policy is referenced also in A.3. Policy Provider Properties, which is also not true anymore
"The name of a default policy provider. If this is not specified then the name of the resource will be used. "

In model description we have
"deprecated" =>

,