patch 8.0.1266: Test_swap_directory was commented out

Problem:    Test_swap_directory was accidentally commented out.
Solution:   Uncomment the test.

src/version.c

@@ -761,6 +761,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1266,
 /**/
     1265,
 /**/