patch 8.1.1817: github contribution text is incomplete

Problem:    Github contribution text is incomplete.
Solution:   Update the text.
diff --git a/src/version.c b/src/version.c
index 5c806a8..287775f 100644
--- a/src/version.c
+++ b/src/version.c
@@ -774,6 +774,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1817,
+/**/
     1816,
 /**/
     1815,