Dolphin backport request

[Nate Graham]

Hello distro packagers!

Those of you shipping or planning to ship Frameworks 5.78, but not 
planning to ship Dolphin 21.04, may want to consider backporting 
https://invent.kde.org/system/dolphin/-/commit/b1cadeba939155282a9fadf7d7b025d6529c489e 
so that your users have a functional knetattach shortcut.

Feel free to backport this into your 20.12.x packages as well, if you're 
already shipping Frameworks 5.78.

For background information, see the discussion in 
https://bugs.kde.org/show_bug.cgi?id=431626.

Nate