Share NBResource between different routes (#149)

This changes the behavior of the Netbird resource so that they can be
shared between routes rather than having one unique created per route.
This is important as we may want to have different route types pointing
to the same service.

Signed-off-by: Philip Laine <philip.laine@gmail.com>

examples/gateway-api/nginx.yaml

@@ -1,61 +0,0 @@
-apiVersion: gateway.networking.k8s.io/v1
-kind: HTTPRoute
-metadata:
-  name: nginx
-  namespace: default
-  labels:
-    app: nginx
-spec:
-  hostnames:
-  - nginx-test-app.eu1.netbird.services
-  parentRefs:
-  - name: netbird
-    namespace: netbird
-  rules:
-    - backendRefs:
-        - name: nginx
-          port: 80
----
-apiVersion: apps/v1
-kind: Deployment
-metadata:
-  name: nginx
-  namespace: default
-  labels:
-    app: nginx
-spec:
-  replicas: 1
-  selector:
-    matchLabels:
-      app: nginx
-  strategy:
-    rollingUpdate:
-      maxSurge: 25%
-      maxUnavailable: 25%
-    type: RollingUpdate
-  template:
-    metadata:
-      labels:
-        app: nginx
-    spec:
-      containers:
-      - image: nginx
-        imagePullPolicy: Always
-        name: nginx
----
-apiVersion: v1
-kind: Service
-metadata:
-  name: nginx
-  namespace: default
-  labels:
-    app: nginx
-spec:
-  type: ClusterIP
-  ports:
-  - name: http
-    port: 80
-    protocol: TCP
-    targetPort: 80
-  selector:
-    app: nginx