LibWeb: Cast unused smart-pointer return values to void

Author: https://github.com/AtkinsSJ
Commit: 7196570f9b
Pull-request: https://github.com/SerenityOS/serenity/pull/11151

Userland/Libraries/LibWeb/WebAssembly/WebAssemblyObject.cpp

@@ -104,7 +104,7 @@ JS_DEFINE_NATIVE_FUNCTION(WebAssemblyObject::validate)
     // Drop the module from the cache, we're never going to refer to it.
     ScopeGuard drop_from_cache {
         [&] {
-            s_compiled_modules.take_last();
+            (void)s_compiled_modules.take_last();
         }
     };