extensions/kde-neon-6: fix XDG_CONFIG_DIRS

[soumyaDghosh]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.70%. Comparing base (654871d) to head (b900513).
Report is 633 commits behind head on main.

❗ There is a different number of reports uploaded between BASE (654871d) and HEAD (b900513). Click for more details.

HEAD has 1 upload less than BASE

Flag	BASE (654871d)	HEAD (b900513)
	2	1

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5104      +/-   ##
==========================================
- Coverage   94.88%   89.70%   -5.18%     
==========================================
  Files         658      341     -317     
  Lines       55189    22589   -32600     
==========================================
- Hits        52364    20263   -32101     
+ Misses       2825     2326     -499     

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[ScarlettGatelyMoore]

Thank you, except this PR needs to be done here: https://invent.kde.org/neon/snap-packaging/snapcraft-desktop-integration

[soumyaDghosh]

Thank you, except this PR needs to be done here: https://invent.kde.org/neon/snap-packaging/snapcraft-desktop-integration

Let's merge it here until it's used from here, else we'll not be able to use the change.