LibJS+LibWeb: Replace GlobalObject with Realm in object constructors

No functional changes - we can still very easily get to the global
object via `Realm::global_object()`. This is in preparation of moving
the intrinsics to the realm and no longer having to pass a global
object when allocating any object.
In a few (now, and many more in subsequent commits) places we get a
realm using `GlobalObject::associated_realm()`, this is intended to be
temporary. For example, create() functions will later receive the same
treatment and are passed a realm instead of a global object.

Userland/Libraries/LibWeb/WebAssembly/WebAssemblyModuleObject.h

@@ -18,7 +18,7 @@ class WebAssemblyModuleObject final : public JS::Object {
     JS_OBJECT(WebAssemblyModuleObject, Object);
 
 public:
-    explicit WebAssemblyModuleObject(JS::GlobalObject&, size_t index);
+    explicit WebAssemblyModuleObject(JS::Realm&, size_t index);
     virtual ~WebAssemblyModuleObject() override = default;
 
     size_t index() const { return m_index; }