OF-3218: Guard against forms with a FORM_TYPE but no value
I don't think this is explicitly defined in a XEP. The closest definition is that of handling forms without a FORM_TYPE. We'll treat these the same: ignore them (but do not stop processing).
OF-3218: Restrict 'well-formed' to XEP definition
Restrict access to this clearly internal method (to avoid generic use) and fail on a stanza that doesn't even contain relevant data.
![dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>](/s/120108/1xwkylm/_/images/icons/spinner.gif){kind=icon}