patch 8.2.4980: when 'shortmess' contains 'A' loading session may still warn

Problem:    When 'shortmess' contains 'A' loading a session may still warn for
            an existing swap file. (Melker Österberg)
Solution:   Keep the 'A' flag to 'shortmess' in the session file.
            (closes #10443)

src/version.c

@@ -746,6 +746,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    4980,
 /**/
     4979,
 /**/