[Gradle Plugin] Allow to set additional property of any type. Useful for Boolean values.

Created by: xsveda

Gradle Plugin's additionalProperties are of type Map<String, String>. When a project tries to set a Boolean property it needs to put it as a String (i.e. "true") which is not evaluated as proper Boolean value by mustache template.

This PR update additionalProperties to Map<String, Any>.

Use case comes from moko-network library: https://github.com/icerockdev/moko-network/issues/59

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