patch 9.0.1444: crash when passing NULL to setcmdline()

Problem:    Crash when passing NULL to setcmdline(). (Andreas Louv)
Solution:   Use tv_get_string() instead of using v_string directly.
            (closes #12231, closes #12227)

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1444,
 /**/
     1443,
 /**/