patch 9.0.1289: a newer version of clang can be used for CI

Problem:    A newer version of clang can be used for CI.
Solution:   Switch from clang-15 to clang-16. (closes #11577)
diff --git a/src/version.c b/src/version.c
index 46ad75c..d7b12b1 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1289,
+/**/
     1288,
 /**/
     1287,