patch 8.1.2275: using "seesion" looks like a mistake

Problem:    Using "seesion" looks like a mistake.
Solution:   Use an underscore to make the function sort first.
diff --git a/src/version.c b/src/version.c
index b6bbf98..44149ff 100644
--- a/src/version.c
+++ b/src/version.c
@@ -742,6 +742,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2275,
+/**/
     2274,
 /**/
     2273,