Remove the limitation 'Policies with modifications' in NIM (#319)

* Remove the limitation 'Policies with modifications'

Created few custom policies having 'modifications block' with various 'entityTypes'. Able to apply these policies to datapath instances in NIM. Hence removing this limitation.

* Update content/nim/nginx-app-protect/setup-waf-config-management.md

Co-authored-by: Alan Dooley <github@adubhlaoi.ch>

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Co-authored-by: Alan Dooley <a.dooley@f5.com>
Co-authored-by: Mike Jang <3287976+mjang@users.noreply.github.com>
Co-authored-by: Alan Dooley <github@adubhlaoi.ch>

Author: 3 people

Diff for: content/nim/nginx-app-protect/setup-waf-config-management.md

@@ -28,8 +28,7 @@ Complete the following prerequisites before proceeding with this guide.
 
 Instance Manager does not support the following NGINX App Protect features:
 
-- [Policies with external references](https://docs.nginx.com/nginx-app-protect-waf/v4/configuration-guide/configuration/#external-references)
-- [Policies with modifications](https://docs.nginx.com/nginx-app-protect-waf/v4/configuration-guide/configuration/#modifying-configurations)
+- [Policies with external references]({{< ref "/nap-waf/v4/configuration-guide/configuration.md#external-references" >}})
 - Custom signatures
 
 ---