Move X-Forwarded-Port variable to the location context

Resolves issue #4038 where the X-Forwarded-Port header would be set to the value of the https listening port if all of the following settings were satisfied:
- The ingress controller was started with a non-default HTTPS port set with the `--https-port` argument
- An ingress is created having:
  - the `nginx.ingress.kubernetes.io/auth-url` annotation set
  - TLS enabled

This commit solves this issue by moving the setting of the `pass_server_port` variable from the server, one level down to the location context.

test/e2e/wait-for-nginx.sh

@@ -22,6 +22,7 @@ fi
 DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 
 export NAMESPACE=$1
+export NAMESPACE_OVERLAY=$2
 
 echo "deploying NGINX Ingress controller in namespace $NAMESPACE"
 
@@ -60,6 +61,21 @@ bases:
 - ../cluster-wide-$NAMESPACE
 EOF
 
+# Use the namespace overlay if it was requested
+if [[ ! -z "$NAMESPACE_OVERLAY" && -d "$DIR/namespace-overlays/$NAMESPACE_OVERLAY" ]]; then
+    echo "Namespace overlay $NAMESPACE_OVERLAY is being used for namespace $NAMESPACE"
+    OVERLAY="$DIR/namespace-overlays/$NAMESPACE"
+    mkdir "$OVERLAY"
+    cat << EOF > "$OVERLAY/kustomization.yaml"
+apiVersion: kustomize.config.k8s.io/v1beta1
+kind: Kustomization
+namespace: $NAMESPACE
+bases:
+- ../../namespace-overlays/$NAMESPACE_OVERLAY
+- ../../cluster-wide-$NAMESPACE
+EOF
+fi
+
 kubectl apply --kustomize "$OVERLAY"
 
 # wait for the deployment and fail if there is an error before starting the execution of any test