patch 8.2.3915: illegal memory access when completing with invalid bytes

Problem:    illegal memory access when completing with invalid bytes.
Solution:   Avoid going over the end of the completion text.
diff --git a/src/version.c b/src/version.c
index 7dd9b49..7b454a6 100644
--- a/src/version.c
+++ b/src/version.c
@@ -750,6 +750,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3915,
+/**/
     3914,
 /**/
     3913,