Update NGF cert-manager docs (#289)

cert-manager has updated their installation command, so we need to update our docs to reflect that change.

Author: sjberman

content/ngf/how-to/traffic-security/integrating-cert-manager.md

@@ -68,9 +68,10 @@ The first step is to deploy cert-manager onto the cluster.
     cert-manager jetstack/cert-manager \
     --namespace cert-manager \
     --create-namespace \
-    --version v1.12.0 \
-    --set installCRDs=true \
-    --set "extraArgs={--feature-gates=ExperimentalGatewayAPISupport=true}"
+    --set config.apiVersion="controller.config.cert-manager.io/v1alpha1" \
+    --set config.kind="ControllerConfiguration" \
+    --set config.enableGatewayAPI=true \
+    --set crds.enabled=true
   ```
 
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