patch 8.2.2348: no check for modified files after focus gained

Problem:    No check for modified files after focus gained. (Mathias Stearn)
Solution:   Call ui_focus_change().
diff --git a/src/version.c b/src/version.c
index 319e65e..cfc9290 100644
--- a/src/version.c
+++ b/src/version.c
@@ -751,6 +751,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2348,
+/**/
     2347,
 /**/
     2346,