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)
diff --git a/src/version.c b/src/version.c
index e41b106..8a64672 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    973,
+/**/
     972,
 /**/
     971,