[POST] /containers/{containerId}/solvers/{solverId}/problemfactchanges

: doesn't allow multiple problemfactchanges although the documentation state that it can (https://docs.optaplanner.org/7.13.0.Final/optaplanner-wb-es-docs/html_single/#_post_containerscontaineridsolverssolveridproblemfactchanges).

An example of the body of such request:

<problem-fact-change class="TaAddTaskProblemFactChange">
	<task>
		<readyTime>0</readyTime>
	</task>
</problem-fact-change>

Both <problem-fact-change> or <problem-fact-changes> have the same effect, submitting one problemFactChange.

Required: Implementing the ability to add multiple problemFactChanges and adding an example in the docs how to do so both in xml and json.