[Interpreter] Remove constant pool type in tests

test/cctest/interpreter/bytecode_expectations/DeleteLookupSlotInEval.golden

 #
 # Autogenerated by generate-bytecode-expectations.
 #
 
 ---
-pool type: string
 execute: yes
 wrap: no
 test function name: f
 
 ---
 snippet: "
   var f;
   var x = 1;
   z = 10;
   function f1() {
     var y;
     eval(\"function t() { delete x; }; f = t; f();\");
   }
   f1();
 "
 frame size: 1
 parameter count: 1
 bytecode array length: 12
 bytecodes: [
   /*   10 E> */ B(StackCheck),
   /*   15 S> */ B(LdaConstant), U8(0),
                 B(Star), R(0),
                 B(CallRuntime), U16(Runtime::kDeleteLookupSlot), R(0), U8(1),
                 B(LdaUndefined),
   /*   25 S> */ B(Return),
 ]
 constant pool: [
-  "x",
+  ONE_BYTE_INTERNALIZED_STRING_TYPE ["x"],
 ]
 handlers: [
 ]
 
 ---
 snippet: "
   var f;
   var x = 1;
   z = 10;
   function f1() {
@@ skipping 30 matching lines @@
 parameter count: 1
 bytecode array length: 11
 bytecodes: [
   /*   10 E> */ B(StackCheck),
   /*   15 S> */ B(LdaConstant), U8(0),
                 B(Star), R(0),
                 B(CallRuntime), U16(Runtime::kDeleteLookupSlot), R(0), U8(1),
   /*   32 S> */ B(Return),
 ]
 constant pool: [
-  "z",
+  ONE_BYTE_INTERNALIZED_STRING_TYPE ["z"],
 ]
 handlers: [
 ]