Remove content hash injection from document preview

[vsgoulart]

What should we do?

On #1340 we created a feature to inject a content hash into the document's URL.
This was created as a temporary fix to make the document preview work on Camunda Tasklist with the document service.

Because this is a Camunda specific feature we should try to find a way to remove it, an option would be to change Camunda Tasklist to have a BFF to manage this hash from the backend.

Why should we do it?

To keep form-js as generic as possible