release version 9.0

Problem:    About time to release Vim 9.0.
Solution:   Update the version number everywhere.
diff --git a/runtime/doc/ft_sql.txt b/runtime/doc/ft_sql.txt
index dde456a..73d619c 100644
--- a/runtime/doc/ft_sql.txt
+++ b/runtime/doc/ft_sql.txt
@@ -1,4 +1,4 @@
-*ft_sql.txt*	For Vim version 8.2.  Last change: 2022 Apr 06
+*ft_sql.txt*	For Vim version 9.0.  Last change: 2022 Apr 06
 
 by David Fishburn