Add support for Gateway API BackendTLSPolicies

pkg/provider/kubernetes/gateway/fixtures/httproute/with_backend_tls_policy.yml

@@ -0,0 +1,78 @@
+---
+kind: GatewayClass
+apiVersion: gateway.networking.k8s.io/v1
+metadata:
+  name: my-gateway-class
+spec:
+  controllerName: traefik.io/gateway-controller
+
+---
+kind: Gateway
+apiVersion: gateway.networking.k8s.io/v1
+metadata:
+  name: my-gateway
+  namespace: default
+spec:
+  gatewayClassName: my-gateway-class
+  listeners: # Use GatewayClass defaults for listener definition.
+    - name: http
+      protocol: HTTP
+      port: 80
+      allowedRoutes:
+        kinds:
+          - kind: HTTPRoute
+            group: gateway.networking.k8s.io
+        namespaces:
+          from: Same
+
+---
+kind: HTTPRoute
+apiVersion: gateway.networking.k8s.io/v1
+metadata:
+  name: http-app-1
+  namespace: default
+spec:
+  parentRefs:
+    - name: my-gateway
+      kind: Gateway
+      group: gateway.networking.k8s.io
+  hostnames:
+    - "foo.com"
+  rules:
+    - matches:
+        - path:
+            type: Exact
+            value: /bar
+      backendRefs:
+        - name: whoami
+          port: 80
+          weight: 1
+          kind: Service
+          group: ""
+
+---
+kind: BackendTLSPolicy
+apiVersion: gateway.networking.k8s.io/v1alpha3
+metadata:
+  name: policy-1
+  namespace: default
+spec:
+  targetRefs:
+    - group: core
+      kind: Service
+      name: whoami
+  validation:
+    hostname: whoami
+    caCertificateRefs:
+      - group: core
+        kind: ConfigMap
+        name: ca-file
+
+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: ca-file
+  namespace: default
+data:
+  ca.crt: "LS0tLS1CRUdJTiBDRVJUSUZJQ0FURS0tLS0tCi0tLS0tRU5EIENFUlRJRklDQVRFLS0tLS0="

pkg/provider/kubernetes/gateway/fixtures/httproute/with_backend_tls_policy_system.yml

@@ -0,0 +1,66 @@
+---
+kind: GatewayClass
+apiVersion: gateway.networking.k8s.io/v1
+metadata:
+  name: my-gateway-class
+spec:
+  controllerName: traefik.io/gateway-controller
+
+---
+kind: Gateway
+apiVersion: gateway.networking.k8s.io/v1
+metadata:
+  name: my-gateway
+  namespace: default
+spec:
+  gatewayClassName: my-gateway-class
+  listeners: # Use GatewayClass defaults for listener definition.
+    - name: http
+      protocol: HTTP
+      port: 80
+      allowedRoutes:
+        kinds:
+          - kind: HTTPRoute
+            group: gateway.networking.k8s.io
+        namespaces:
+          from: Same
+
+---
+kind: HTTPRoute
+apiVersion: gateway.networking.k8s.io/v1
+metadata:
+  name: http-app-1
+  namespace: default
+spec:
+  parentRefs:
+    - name: my-gateway
+      kind: Gateway
+      group: gateway.networking.k8s.io
+  hostnames:
+    - "foo.com"
+  rules:
+    - matches:
+        - path:
+            type: Exact
+            value: /bar
+      backendRefs:
+        - name: whoami
+          port: 80
+          weight: 1
+          kind: Service
+          group: ""
+
+---
+kind: BackendTLSPolicy
+apiVersion: gateway.networking.k8s.io/v1alpha3
+metadata:
+  name: policy-1
+  namespace: default
+spec:
+  targetRefs:
+    - group: core
+      kind: Service
+      name: whoami
+  validation:
+    hostname: whoami
+    wellKnownCACertificates: System