Fix handling of data packages in manifest.xml

If for any reason the variable VERSION was set before invoking gaudi_project and the project used version patterns for data packages, the manifest.xml was badly generated and looked like this:

...
  <used_data_pkgs>
    <package name="FieldMap" version="*" />
    <package name="VERSION" version="*" />
    <package name="v5r*" version="*" />
    ...
  </used_data_pkgs>
...

This MR fixes the problem.