fix(borders): destroy hpen and hbrush objects

This commit ensures that HPEN and HBRUSH objects created to draw window
borders are explicitly destroyed with calls to DeleteObject after
EndPaint has been called.

re #855

komorebi/src/border_manager/border.rs

@@ -27,6 +27,7 @@ use windows::Win32::Foundation::LRESULT;
 use windows::Win32::Foundation::WPARAM;
 use windows::Win32::Graphics::Gdi::BeginPaint;
 use windows::Win32::Graphics::Gdi::CreatePen;
+use windows::Win32::Graphics::Gdi::DeleteObject;
 use windows::Win32::Graphics::Gdi::EndPaint;
 use windows::Win32::Graphics::Gdi::InvalidateRect;
 use windows::Win32::Graphics::Gdi::Rectangle;
@@ -210,6 +211,8 @@ impl Border {
                             }
                         }
                         EndPaint(window, &ps);
+                        DeleteObject(hpen);
+                        DeleteObject(hbrush);
                         ValidateRect(window, None);
                     }