patch 8.2.0828: Travis: regexp patttern doesn't work everywhere

Problem:    Travis: regexp patttern doesn't work everywhere.
Solution:   Use [:blank:] instead of \b. (Ozaki Kiichi, closes #6146)

src/version.c

@@ -746,6 +746,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    828,
 /**/
     827,
 /**/