Change SDK name of Sentry Native for Flutter

[marandaneto]

Description

Right now it is sentry.native.android and this is set at compile time.
Ideally, this would be sentry.native.android.flutter or just sentry.native.flutter.

[vaind]

1. The right name would be sentry.native.android.flutter from what I remember doing this in Unity, see https://github.com/getsentry/sentry-unity/blob/8420c95a3def1d6b611f031070d6977f3e574397/Directory.Build.targets#L190
2. Unless there has been new development in changing this in sentry-native, it must be changed at compile time which means we cannot set it for Flutter specifically without building the android SDK. Currently, the flutter plugin just depends on package published by sentry-java https://github.com/getsentry/sentry-unity/blob/8420c95a3def1d6b611f031070d6977f3e574397/Directory.Build.targets#L190

[marandaneto]

Created getsentry/sentry-native#821
Since sentry-native is transitioning from one team (former Native team) to the Mobile team (the one I work for), let me check what we can do.

[marandaneto]

getsentry/sentry-native#821 is merged, now the Android SDK has to offer a public API or append .android automatically.

[marandaneto]

Now its possible to set the sentry-native SDK name at runtime getsentry/sentry-java#2704
This is the last missing bit.