pidgin/pidgin

Update COPYRIGHT file
release-2.x.y
2022-05-10, Richard Laager
758a7925a920
Update COPYRIGHT file

I audited the Copyright lines in Pidgin 2. This brings the COPYRIGHT
file in line.

Reviewed at https://reviews.imfreedom.org/r/1425/
How to build Pidgin for Windows using MinGW
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For the latest build instructions, please refer to:
http://developer.pidgin.im/wiki/BuildingWinPidgin