Purchases.isConfigured always returns true

[x] I have updated Purchases SDK to the latest version
[x] I have read the Contribution Guidelines
[x] I have searched the Community
[x] I have read docs.revenuecat.com
[x] I have searched for existing Github issues

Environment

[x] Output of flutter doctor


Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel stable, 3.24.4, on macOS 15.0 24A335 darwin-arm64, locale en-IN)
[✓] Android toolchain - develop for Android devices (Android SDK version 34.0.0)
[✓] Xcode - develop for iOS and macOS (Xcode 16.1)
[✓] Chrome - develop for the web
[✓] Android Studio (version 2024.1)
[✓] Connected device (10 available)
[✓] Network resources


- [x] Version of `purchases-flutter`
`>=3.24.0`
- [x] Testing device version 
`Android API 34`
- [x] How often the issue occurs- every one of your customers is impacted? Only in dev?
    - Only in dev
- [x] [Debug logs](https://docs.revenuecat.com/docs/debugging) that reproduce the issue

PurchasesError(code=InvalidCredentialsError, underlyingErrorMessage=Invalid API Key., message='There was a credentials issue. Check the underlying error for more details.')



- [x] Steps to reproduce, with a description of expected vs. actual behavior
**Other information** (e.g. stacktraces, related issues, suggestions how to fix, links for us to have context, eg. stackoverflow, etc.)
1) Added dummy Api Key `dummy`.
2) Run the app.
3) Check that the message is printed in the console.
4) Hot restart the app.
5) Still That error

## Describe the bug ##
I have added a dummy API key in `Purchases.configure(configuration)` and encountered error logs. However, when I call `Purchases.isConfigured`, it returns `true`. Please help resolve this issue. Note that it works fine when the API key is empty.

## Additional context ##

I've tried multiple times, but the issue persists.

RevenueCat / purchases-flutter

Purchases.isConfigured always returns true #1210

Environment