patch 8.2.3668: messages may be corrupted

Problem:    Messages may be corrupted.
Solution:   Use another buffer instead of IObuff. (Yegappan Lakshmanan,
            closes #9195)
diff --git a/src/version.c b/src/version.c
index 42cfafa..a225e18 100644
--- a/src/version.c
+++ b/src/version.c
@@ -758,6 +758,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3668,
+/**/
     3667,
 /**/
     3666,