[KotlinTest] EntryPointGeneration.groovy to Kotlin (#64)

Part of #58

Author: Nava2

src/test/groovy/org/assertj/generator/gradle/parameter/EntryPointGeneration.groovy

@@ -2,9 +2,14 @@ package org.assertj.generator.gradle
 
 import org.intellij.lang.annotations.Language
 import java.io.File
+import java.nio.file.Path
+import kotlin.io.path.writeText
 
 fun File.writeJava(@Language("java") content: String): Unit = writeText(content.trimIndent())
+fun Path.writeJava(@Language("java") content: String): Unit = writeText(content.trimIndent())
 
 fun File.writeGroovy(@Language("groovy") content: String): Unit = writeText(content.trimIndent())
+fun Path.writeGroovy(@Language("groovy") content: String): Unit = writeText(content.trimIndent())
 
 fun File.writeKotlin(@Language("kotlin") content: String): Unit = writeText(content.trimIndent())
+fun Path.writeKotlin(@Language("kotlin") content: String): Unit = writeText(content.trimIndent())