Add posthog tracking for key backup toasts (#31195)

* Add tracking for setting up key backups.

* fix lint

* Update @matrix-org/analytics-events to 0.30.0

package.json

@@ -87,7 +87,7 @@
         "@fontsource/inconsolata": "^5",
         "@fontsource/inter": "^5",
         "@formatjs/intl-segmenter": "^11.5.7",
-        "@matrix-org/analytics-events": "^0.29.2",
+        "@matrix-org/analytics-events": "^0.30.0",
         "@matrix-org/emojibase-bindings": "^1.3.4",
         "@matrix-org/react-sdk-module-api": "^2.4.0",
         "@matrix-org/spec": "^1.7.0",