devel/py-pipdeptree: Fix runtime

At runtime the program crashes due to an error like the following:
ImportError: cannot import name 'version' from 'pipdeptree.version'

Which is caused due to the new template format of the setuptools_scm.
Currently this is just a dirty hack to support older(<7) setuptools_scm
format.

PR: 274101
Reported by: vedran@miletic.net