patch 9.0.0973: Kitty keyboard protocol key with NumLock not decoded

Problem:    Kitty keyboard protocol key not decoded when it has an unsupported
            modifier, such as NumLock.
Solution:   Accept a key with any modifier. (closes #11638)

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    973,
 /**/
     972,
 /**/