bug#55186: package-definition-location is wrong for inherited packages

[Maxim Cournoyer]

Hi Guix,

Here's another problem with source location I've discovered when
attempting to locate the source of `python2-pytest-warnings', which
reads like:

--8<---------------cut here---------------start------------->8---
(define-public python2-pytest-warnings
  (package (inherit (package-with-python2
                     (strip-python2-variant python-pytest-warnings)))
           (properties `((superseded . ,python2-pytest)))))
--8<---------------cut here---------------end--------------->8---

The define-public line is at line 2569, but:

--8<---------------cut here---------------start------------->8---
(define package (car (find-packages-by-name "python2-pytest-warnings")))
(package-definition-location package) location->source-properties)
--8<---------------cut here---------------end--------------->8---

returns 2570, the line below.

Thanks,

Maxim