vim-patch:8.2.5155: in diff mode windows may get out of sync

Problem:    In diff mode windows may get out of sync. (Gary Johnson)
Solution:   Avoid that the other window scrolls for 'cursorbind'.
a315ce1f32

src/nvim/move.c

@@ -2271,7 +2271,13 @@ void do_check_cursorbind(void)
         int restart_edit_save = restart_edit;
         restart_edit = true;
         check_cursor();
-        validate_cursor();
+
+        // Avoid a scroll here for the cursor position, 'scrollbind' is
+        // more important.
+        if (!curwin->w_p_scb) {
+          validate_cursor();
+        }
+
         restart_edit = restart_edit_save;
       }
       // Correct cursor for multi-byte character.