Overhaul GenericScimResource documentation.

Updated the documentation for GenericScimResource objects to provide
clearer messaging and better examples on how the class can help define
a new resource type, as well as how clients can leverage the library
methods effectively. The Javadocs have been standardized for consistent
messaging.

This change includes some test updates to validate some of the behavior
that was documented previously, but did not have coverage.

Reviewer: vyhhuang
Reviewer: dougbulkley

JiraIssue: DS-49314

CHANGELOG.md

@@ -36,6 +36,11 @@ The default value of `APPEND_NEW_PATCH_VALUES_PROPERTY` is `true`, which will al
 value (i.e., email) on the multi-valued attribute instead of updating an existing value/email.
 This matches the behavior of the SDK since the 3.0.0 release.
 
+Refreshed the documentation of the `GenericScimResource` class to provide better insight on how it
+can be used to define resource types for objects that don't have a strongly defined schema. The
+class-level Javadoc describes how to interface with the object effectively, and the methods now
+provide clearer examples of how they can be used.
+
 ## v3.1.0 - 2024-Jun-25
 Updated all classes within the UnboundID SCIM 2 SDK to utilize `@Nullable` and `@NotNull`
 annotations for all non-primitive input parameters, member variables, and return values. These