REGTEST: Add option to use HTX prefixed by the macro 'no-htx'

So some tests have been removed.
diff --git a/reg-tests/lua/b00000.vtc b/reg-tests/lua/b00000.vtc
index 5d396a7..577329e 100644
--- a/reg-tests/lua/b00000.vtc
+++ b/reg-tests/lua/b00000.vtc
@@ -46,6 +46,7 @@
 
     frontend fe1
         mode http
+        ${no-htx} option http-use-htx
         bind "fd@${fe1}"
         default_backend b1
 
@@ -53,6 +54,7 @@
 
     backend b1
         mode http
+        ${no-htx} option http-use-htx
         server s1 ${s1_addr}:${s1_port}
 
 } -start