This is to avoid any unnecessary reconciliation for non-GAMMA HTTPRoute:

- Explicitly check if Kind and Group are not nil, as per the Gateway API
  spec, the nil values is meant for Gateway.
- Add GAMMA check for backend services and listening service.

Additionally, one small correction on Reason status is added to make
sure that the space character is not used.

```
2024-06-06T05:34:31.583996151Z time="2024-06-06T05:34:31Z" level=error msg="Reconciler error" HTTPRoute="{attaches-to-wildcard-example-com-with-hostname-intersection gateway-conformance-infra}" controller=httproute controllerGroup=gateway.networking.k8s.io controllerKind=HTTPRoute error="failed to update HTTPRoute status: HTTPRoute.gateway.networking.k8s.io \"attaches-to-wildcard-example-com-with-hostname-intersection\" is invalid: parents[0].conditions[0].reason: Invalid value: \"Invalid HTTPRoute\": parents[0].conditions[0].reason in body should match '^[A-Za-z]([A-Za-z0-9_,:]*[A-Za-z0-9_])?$'" name=attaches-to-wildcard-example-com-with-hostname-intersection namespace=gateway-conformance-infra reconcileID="\"2c43d9eb-52ad-4344-b0ff-e58c227221fb\"" subsys=controller-runtime
```

Relates: 363fdd4ff951e02ebf666b1dccf17d0dfb5a0f47
Signed-off-by: Tam Mach <tam.mach@cilium.io>