patch 8.2.3347: check for legacy script is incomplete

Problem:    Check for legacy script is incomplete. (Naohiro Ono)
Solution:   Also check the :legacy modifier.  Use for string concatenation
            with "." and others (issue #8756)

src/version.c

@@ -755,6 +755,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    3347,
 /**/
     3346,
 /**/