[#9020] Prevent xPDOZip from attempting to add empty targets

Was attempting to add targets defined as '/' previously
[#9629] Fix notice in xPDOConnection::getOption() when $options not an array
Merge remote-tracking branch 'xpdo/develop' into develop

* xpdo/develop:
  [#9629] Fix notice in xPDOConnection::getOption() when $options not an array
  [#9020] Prevent xPDOZip from attempting to add empty targets