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/Runtime/Promise.cpp

@@ -64,7 +64,7 @@ Promise::ResolvingFunctions Promise::create_resolving_functions()
     auto& realm = *vm.current_realm();
 
     // 1. Let alreadyResolved be the Record { [[Value]]: false }.
-    auto already_resolved = vm.heap().allocate_without_realm<AlreadyResolved>();
+    auto already_resolved = vm.heap().allocate<AlreadyResolved>();
 
     // 2. Let stepsResolve be the algorithm steps defined in Promise Resolve Functions.
     // 3. Let lengthResolve be the number of non-optional parameters of the function definition in Promise Resolve Functions.