[ignition] Expect 'I' for signed bytecode operands

test/cctest/interpreter/bytecode_expectations/CallNew.golden

 #
 # Autogenerated by generate-bytecode-expectations.
 #
 
 ---
 wrap: no
 test function name: f
 
 ---
 snippet: "
@@ skipping 23 matching lines @@
   function f() { return new bar(3); }
   f();
 "
 frame size: 2
 parameter count: 1
 bytecode array length: 18
 bytecodes: [
   /*   58 E> */ B(StackCheck),
   /*   63 S> */ B(LdaGlobal), U8(0), U8(4),
                 B(Star), R(0),
-                B(LdaSmi), U8(3),
+                B(LdaSmi), I8(3),
                 B(Star), R(1),
                 B(Ldar), R(0),
   /*   70 E> */ B(New), R(0), R(1), U8(1), U8(2),
   /*   82 S> */ B(Return),
 ]
 constant pool: [
   ONE_BYTE_INTERNALIZED_STRING_TYPE ["bar"],
 ]
 handlers: [
 ]
 
 ---
 snippet: "
   function bar(w, x, y, z) {
     this.value = 18;
     this.x = x;
     this.y = y;
     this.z = z;
   }
   function f() { return new bar(3, 4, 5); }
   f();
 "
 frame size: 4
 parameter count: 1
 bytecode array length: 26
 bytecodes: [
   /*  100 E> */ B(StackCheck),
   /*  105 S> */ B(LdaGlobal), U8(0), U8(4),
                 B(Star), R(0),
-                B(LdaSmi), U8(3),
+                B(LdaSmi), I8(3),
                 B(Star), R(1),
-                B(LdaSmi), U8(4),
+                B(LdaSmi), I8(4),
                 B(Star), R(2),
-                B(LdaSmi), U8(5),
+                B(LdaSmi), I8(5),
                 B(Star), R(3),
                 B(Ldar), R(0),
   /*  112 E> */ B(New), R(0), R(1), U8(3), U8(2),
   /*  130 S> */ B(Return),
 ]
 constant pool: [
   ONE_BYTE_INTERNALIZED_STRING_TYPE ["bar"],
 ]
 handlers: [
 ]