LPS-48332 Markdown importer should use Knowledge Base attachments and not Documents and Media
LPS-48332 add a : before an exception message
LPS-48332 Notice that KBArticleImporterUtil uses "name" and "fileName" and KBArticleMarkdownConverter uses "imageName" all to mean the same thing. So I renamed it to just "imageFileName".
LPS-48332 Remove exceptions that are not thrown