testing/sdrangel: upgrade to 7.22.5

• https://github.com/f4exb/sdrangel/releases/tag/v7.22.5
• https://github.com/f4exb/sdrangel/releases/tag
• https://github.com/f4exb/sdrangel/compare/v7.22.0...v7.22.5

I may also look at switching to Qt6 but, first, let's see if it builds by just bumping to the latest release