patch 8.1.0303: line2byte() is wrong for last line with 'noeol'

Problem:    line2byte() is wrong for last line with 'noeol' and 'nofixeol'.
Solution:   Fix off-by-one error. (Shane Harper, closes #3351)
diff --git a/src/version.c b/src/version.c
index 42a81cc..d382ff3 100644
--- a/src/version.c
+++ b/src/version.c
@@ -795,6 +795,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    303,
+/**/
     302,
 /**/
     301,