Always use nocheck="yes" for consistency

tests/data/test2003

@@ -15,7 +15,7 @@ multiprotocol
 #
 # Server-side
 <reply>
-<data1 nocheck="1">
+<data1 nocheck="yes">
 HTTP/1.1 200 OK
 Date: Thu, 09 Nov 2010 14:49:00 GMT
 Server: test-server/fake
@@ -29,7 +29,7 @@ Funny-head: yesyes
 
 -foo-
 </data1>
-<data2 nocheck="1">
+<data2 nocheck="yes">
 data
     to
       see
@@ -37,7 +37,7 @@ that FTP
 works
   so does it?
 </data2>
-<data3 nocheck="1">
+<data3 nocheck="yes">
 a chunk of
 data
 returned