REGTESTS: Do not use REQUIRE_VERSION for HAProxy 2.5+ (2)

Introduced in:

18c13d3bd MEDIUM: http-ana: Add a proxy option to restrict chars in request header names

see also:

fbbbc33df REGTESTS: Do not use REQUIRE_VERSION for HAProxy 2.5+
diff --git a/reg-tests/http-rules/restrict_req_hdr_names.vtc b/reg-tests/http-rules/restrict_req_hdr_names.vtc
index 28a10d3..a3a9593 100644
--- a/reg-tests/http-rules/restrict_req_hdr_names.vtc
+++ b/reg-tests/http-rules/restrict_req_hdr_names.vtc
@@ -1,5 +1,5 @@
 varnishtest "http-restrict-req-hdr-names option tests"
-#REQUIRE_VERSION=2.6
+feature cmd "$HAPROXY_PROGRAM -cc 'version_atleast(2.6-dev0)'"
 
 # This config tests "http-restrict-req-hdr-names" option