bug(android): post-update error - onPackageInstalled where context is null.

Sentry Issue: [KEYMAN-ANDROID-4AJ](https://keyman.sentry.io/issues/4615522990/?referrer=github_integration)

```
onPackageInstalled where context is null.
```

@jahorton here. I ran into this while testing #10017 with a version-edited .kmp. I can verify that the following line was reached via debugger when reproducing it:

https://github.com/keymanapp/keyman/blob/864f37884449bac22aff642c0647b61051847898/android/KMEA/app/src/main/java/com/keyman/engine/logic/ResourcesUpdateTool.java#L524

Repro (as done via Android Studio device emulation):
- Go to jahorton.github.io
- Download the version-edited khmer_angkor.kmp and install it within the Keyman app.
- Force-kill the Keyman app.
- Restart the Keyman app.
- Go to Settings > Installed Languages > Central Khmer -> Khmer Angkor.
- Click on the "Update Available" icon/link thing.
- Exit back to the main screen of the app.
- Wait until notifications appear.

The download process took surprising long to complete when I did this - I had ample time to "exit back" - and my goal for testing #10017 was to verify that the host-page would reset... which is best done by actually having the keyboard host-page active and viewable. (I actually had an 'inspector' open via Chrome to validate that the console was reset... which is suspended unless the host-page is active.) I think it took somewhere between 30 sec to 1 minute for the update's download to complete? Just in case that's relevant.