Update the docs to use new policies in place of the legacy ones

[bartsmykla]

Description

In all places where the docs were using legacy policies to suggest some behavior or to show examples we should replace it with the new policies instead.

• [x] https://github.com/kumahq/kuma-website/pull/1607
• [x] https://github.com/kumahq/kuma-website/pull/1608
• [ ] https://github.com/kumahq/kuma-website/pull/1613
• [x] Update Networking / Non-mesh traffic page with new policies - @slonka https://github.com/kumahq/kuma-website/pull/1615
  • Use MeshProxyPatch instead of ProxyTemplate
• [ ] @michaelbeaumont Update/Replace Explore / Gateway page with new policies
  • WIP https://github.com/kumahq/kuma-website/pull/1582
• [x] https://github.com/kumahq/kuma-website/pull/1614
• [X] @slonka - https://github.com/kumahq/kuma-website/pull/1618 - Update Kuma in Production / Create multiple service meshes in a cluster page with new policies
  • Link to new policies
  • Replace TrafficRoute from the example with new policies

[slonka]

I'll take

Update [Networking / Non-mesh traffic](https://kuma.io/docs/dev/networking/non-mesh-traffic/) page with new policies
Use MeshProxyPatch instead of ProxyTemplate