set_role_definition for Key Vault should reorder parameters

[heaths]

Based on our API unification review, Python should reorder parameters accordingly:

1. role_scope : required KeyVaultRoleScope
2. role_definition_name : optional UUID - autogenerate if None, but document that if customers don't provide a fixed value of an existing definition, a new one will be created.
3. role_name : optional string - friendly display name; document that it defaults to role_definition_name if absent
4. description : optional string - long-form description of role definition
5. permissions : optional list of KeyVaultPermission
6. assignable_scopes : optional list of KeyVaultRoleScope

We'll use this issue to track any changes to the API from other languages' issues. .NET, Java, and JavaScript should consider a KeyVaultRoleDefinitionParameters as an options bag given the number of possible arguments. Currently, the "Parameters" suffix is the guideline if it contains required parameters, but there is some question about this.

/cc @KrzysztofCwalina @tg-msft @annatisch @johanste @JonathanGiles @bterlson

[heaths]

Alternatively, we could all probably unify on making the first two parameters positional arguments in the method, and the rest in an options bag/kwargs which should be in line with our respective guidelines. The first two are the only two that are really required (the second is required, but we can / will autogenerate). Thoughts?

[heaths]

After discussing with an architect, our best course of action for now would be to create an "Options" class like RoleDefinitionOptions or even CreateOrUpdateRoleDefinitionOptions, which follows our normal .NET guidelines.

Having separate constructors/builders would also help make the documented behavior regarding roleDefinitionName more obvious. Thus, we'd have (using .NET as an example):

public class CreateOrUpdateRoleDefinitionOptions
{
  public RoleDefinitionOptions(KeyVaultRoleScope roleScope);
  public RoleDefinitionOptions(KeyVaultRoleScope roleScope, Guid roleDefinitionName);
  public KeyVaultRoleScope RoleScope {get;}
  public Guid RoleDefinitionName {get;}
  // getters and setters on everything else
}
public class KeyVaultAccessControlClient
{
  public Response<KeyVaultRoleDefinition> CreateOrUpdateRoleDefinition(CreateOrUpdateRoleDefinitionOptionsoptions, CancellationToken cancellationToken = default);
  public Response<KeyVaultRoleDefinition> CreateOrUpdateRoleDefinition(KeyVaultRoleScope roleScope, Guid? roleDefinitionName = null, CancellationToken cancellationToken = default);
}

[JonathanGiles]

The code in your previous comment is suitable for translation and usage in Java too.