fix: make flagd config EvaluatorType public

[detached]

Make flagd config EvaluatorType public

This PR makes the EvaluatorType interface public, so that the implementing enums can then be used in Kotlin.

Related Issues

Fixes #1013

Notes

This bug in Kotlin prevents the usage of that enums in a Kotlin project: https://youtrack.jetbrains.com/issue/KT-11700

How to test

Code like the following should not lead to a runtime error:

    fun getFlagdProvider(): FlagdProvider = FlagdProvider(
        FlagdOptions.builder()
            .resolverType(Config.Resolver.IN_PROCESS)
            .build()
    )

[toddbaert]

@detached Hey, happy to accept this, but the CNCF policy requires all commits to be signed off. Please do a git commit --amend --signoff and force push your changes back up. (see the failed DCO check): https://github.com/open-feature/java-sdk-contrib/pull/1014/checks?check_run_id=31296104106

[detached]

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