patch 8.2.1904: still using default option values after using ":badd +1"

Problem:    Still using default option values after using ":badd +1".
Solution:   Find a window where options were set.  Don't set the window when
            using ":badd".
diff --git a/src/testdir/test_buffer.vim b/src/testdir/test_buffer.vim
index 2f0f312..a743f18 100644
--- a/src/testdir/test_buffer.vim
+++ b/src/testdir/test_buffer.vim
@@ -366,7 +366,7 @@
   new SomeNewBuffer
   setlocal numberwidth=3
   wincmd p
-  badd SomeNewBuffer
+  badd +1 SomeNewBuffer
   new SomeNewBuffer
   call assert_equal(3, &numberwidth)
   close