feat: add Window::is_resizable (#2171)

* feat: add `Window::is_resizable`

* move it right after `set_resizable`

src/platform_impl/android/mod.rs

@@ -543,6 +543,10 @@ impl Window {
 
     pub fn set_resizable(&self, _resizeable: bool) {}
 
+    pub fn is_resizable(&self) -> bool {
+        false
+    }
+
     pub fn set_minimized(&self, _minimized: bool) {}
 
     pub fn set_maximized(&self, _maximized: bool) {}