(MODULES-2023) - autorequire the file we are generating

concat_file generates a file resource which will manage the content,
while the interface for requirements is Concat[] or at least
Concat_file[]. The file is currently flowing within the graph
without any dependency. However, so that require and notifies are
working properly, the file must be present before the concat_file
resource is finished being managed and potentially other resources
depending on that one are being managed.

This also makes the copy & paste from looking for the parent
directory as originaly described within MODULES-2023 obsolete, as
this will be handled by the file itself.