Update Candidate.kt

Author: daymxn

firebase-vertexai/src/main/kotlin/com/google/firebase/vertexai/type/Candidate.kt

@@ -21,7 +21,6 @@ package com.google.firebase.vertexai.type
 import com.google.firebase.vertexai.common.util.FirstOrdinalSerializer
 import java.util.Calendar
 import kotlinx.serialization.ExperimentalSerializationApi
-import kotlinx.serialization.InternalSerializationApi
 import kotlinx.serialization.KSerializer
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable