Unable to use multi-file endpoints dynamically

[kostas-jonauskas]

When passing a single file for a converter that supports multiple files as input, the library throws an exception:

Therefore, we cannot use it in dynamic environments, like running user workflows. If the user adds an IMAGES to PDF endpoint, we cannot force him to strictly pass multiple files to run this workflow. Whether he passes a single image or multiple images, we must return to him a PDF. REST-API supports this, so the library should not throw an exception.

For example, a workflow like this:

1. DOCX to PNG
2. IMAGES to PDF

Would fail if the initial DOCX file contains a single page, and the first conversion results in a single image.

[tomasr78]

@kostas-jonauskas This will be possible when we migrate to V3 CARA version.