v8.6.0

Added

• Add additional grouping discriminator property to events #2544
• (react-native) Handle additional grouping discriminator #2557
• (electron) Handle additional grouping discriminator #2561

Changed

• Update bugsnag-cocoa to v6.33.1 #2552
• Update bugsnag-android to v6.18.0 #2556

Fixed

• (plugin-window-onerror) Guard against errors when trying to call previous handler #2551