Content EXIM: getExistingDocumentPath doesn't check if argument location is existing path

Method org.onehippo.forge.content.exim.core.impl.WorkflowDocumentManagerImpl#getExistingDocumentPath as an argument 'documentPath'.

The documentPath value is encoded as node path, then resulting node (if any) is returned.

This fails when using WorkflowDocumentManagerImpl#translateDocument on document "/content/documents/translationsaddondemo/blog/authors/Hippo Author" that comes with Essentials:

 Caused by: java.lang.IllegalArgumentException: Source document doesn't exist at '/content/documents/translationsaddondemo/blog/authors/Hippo Author'.

Suggestion to do a simple getSession().nodeExists(documentLocation) first.