Revert "LibJS: Add bytecode instruction handles"

This reverts commit a01bd35c67.

This broke simple programs like:

function sum(a, b) { return a + b; }
console.log(sum(1, 2));

Userland/Libraries/LibJS/Bytecode/Instruction.cpp

@@ -4,7 +4,6 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
-#include <LibJS/Bytecode/Block.h>
 #include <LibJS/Bytecode/Instruction.h>
 #include <LibJS/Bytecode/Op.h>