[PowerAssert] Add codegen tests

plugins/power-assert/testData/codegen/junit5/JunitAssertTrueMessageVariable.kt

@@ -0,0 +1,9 @@
+// FUNCTION: org.junit.jupiter.api.Assertions.assertTrue
+// WITH_JUNIT5
+
+import org.junit.jupiter.api.Assertions.assertTrue
+
+fun box() = expectThrowableMessage {
+    val message = "Message:"
+    assertTrue(1 != 1, message)
+}