Update lib/private/Memcache/KeyValueCache.php

Co-authored-by: Côme Chilliet <91878298+come-nc@users.noreply.github.com>
Signed-off-by: Ferdinand Thiessen <opensource@fthiessen.de>

Author: susnux

lib/private/Memcache/KeyValueCache.php

@@ -23,7 +23,7 @@
  */
 class KeyValueCache extends Cache implements IMemcacheTTL {
 	/** name => [script, sha1] */
-	public const LUA_SCRIPTS = [
+	private const LUA_SCRIPTS = [
 		'dec' => [
 			'if redis.call("exists", KEYS[1]) == 1 then return redis.call("decrby", KEYS[1], ARGV[1]) else return "NEX" end',
 			'720b40cb66cef1579f2ef16ec69b3da8c85510e9',