patch 8.1.0260: no LGTM logo in README file

Problem:    No LGTM logo in README file.
Solution:   Add one. (Bas van Schaik, closes #3305)
diff --git a/src/version.c b/src/version.c
index dadb978..962d173 100644
--- a/src/version.c
+++ b/src/version.c
@@ -795,6 +795,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    260,
+/**/
     259,
 /**/
     258,