gnome-software 3.22.6 release.

• Add support for RuntimeRepo in flatpakref files
• Avoid requesting elevated privileges just for viewing flatpakref details
• Fix launching flatpak apps after updating
• Install needed Flatpak runtimes when updating an app
• Do not show related flatpak runtimes as separate entries
• Improve internal locking, hopefully fixing a few hard-to-debug crashes
• Fix a large memory leak in the steam plugin
• Add keywords to match web apps and input methods
• Fix a few user interface papercuts

This release also updates translations.