feat(core,windows): add PluginRegistry to Windows

[Lyokone]

Description

To match the PluginRegistry of other native implementation, adding the PluginRegistry to Windows.

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[cynthiajoan]

This is not the recommend pattern. We usually do this in test code but not production ones, especially inside a for loop. I cannot find getPluginConstantsForFirebaseApp() and didReinitializeFirebaseCore() inside existing code, can you point me where they are so maybe we can think of a better way to handle this async operation.