Update hips/hip-9999.md

Co-authored-by: Scott Rigby <scott@r6by.com>
Signed-off-by: Andrew Suderman <andy@suderman.dev>
Signed-off-by: Andy Suderman <andy@suderman.dev>

Author: sudermanjr

hips/hip-9999.md

@@ -1,5 +1,5 @@
 ---
-hip: 9999
+hip: 0018
 title: "Add Repository URL and tarball digest to a chart's release metadata"
 authors: [ "Luke Reed <luke@lreed.net>", "Andy Suderman <andy@suderman.dev> ]
 created: "2021-11-24"