script: propagate &mut JSContext in DebuggerGlobalScope::fire_add_debugee (#44476)

Propagate `&mut JSContext` in `DebuggerGlobalScope::fire_add_debugee`

Testing: Successful build is enough
Fixes: Part of #42638 

Opened to reduces the complexity of #44254

Signed-off-by: Emmanuel Paul Elom <elomemmanuel007@gmail.com>

components/script/script_thread.rs

@@ -3446,12 +3446,8 @@ impl ScriptThread {
             incomplete.theme,
             self.this.clone(),
         );
-        self.debugger_global.fire_add_debuggee(
-            CanGc::from_cx(cx),
-            window.upcast(),
-            incomplete.pipeline_id,
-            None,
-        );
+        self.debugger_global
+            .fire_add_debuggee(cx, window.upcast(), incomplete.pipeline_id, None);
 
         let mut realm = enter_auto_realm(cx, &*window);
         let cx = &mut realm;