patch 8.2.4489: failing test for comparing v:null with number

Problem:    Failing test for comparing v:null with number.
Solution:   Allow comparing v:null with number in legacy script.
            (Ken Takata, closes #9873)  Also do this for float.
diff --git a/src/version.c b/src/version.c
index 3918e74..b212379 100644
--- a/src/version.c
+++ b/src/version.c
@@ -755,6 +755,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    4489,
+/**/
     4488,
 /**/
     4487,