Fix VM memory allocation optimizations by reducing what we allocate on the heap

internal/object/object_test.go

@@ -3,10 +3,10 @@ package object
 import "testing"
 
 func TestStringHashKey(t *testing.T) {
-	hello1 := &String{Value: "Hello World"}
-	hello2 := &String{Value: "Hello World"}
-	diff1 := &String{Value: "My name is johnny"}
-	diff2 := &String{Value: "My name is johnny"}
+	hello1 := String{Value: "Hello World"}
+	hello2 := String{Value: "Hello World"}
+	diff1 := String{Value: "My name is johnny"}
+	diff2 := String{Value: "My name is johnny"}
 
 	if hello1.HashKey() != hello2.HashKey() {
 		t.Errorf("string with same content have different hash keys")