LibJS+LibWeb: Rename Heap::allocate_without_realm to Heap::allocate

Now that the heap has no knowledge about a JavaScript realm and is
purely for managing the memory of the heap, it does not make sense
to name this function to say that it is a non-realm variant.

Libraries/LibJS/Bytecode/Generator.cpp

@@ -422,7 +422,7 @@ CodeGenerationErrorOr<NonnullGCPtr<Executable>> Generator::compile(VM& vm, ASTNo
         label.set_address(block_offsets.get(block).value());
     }
 
-    auto executable = vm.heap().allocate_without_realm<Executable>(
+    auto executable = vm.heap().allocate<Executable>(
         move(bytecode),
         move(generator.m_identifier_table),
         move(generator.m_string_table),