Update README.md

Author: frankois944

README.md

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 # KTViewModelBuilder
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+[![codecov](https://codecov.io/github/frankois944/KTViewModelBuilder/branch/main/graph/badge.svg?token=X25DPW3QJL)](https://codecov.io/github/frankois944/KTViewModelBuilder)
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 A macro to use inside a Kotlin multiplatform project for wrapping a Kotlin ViewModel into a SwiftUI ObservableObject, based on the [SKIE library](https://skie.touchlab.co/).
 
 The goal of this macro is to increase the iOS development experience by removing the complexity of using a Kotlin ViewModel inside an iOS application written in Swift and also respecting the Lifecycle.