Add callout for instances where NO_PROXY requires an asterisk (#987)

<!-- Explain the changes introduced in your PR -->
This change adds a nuanced item where some customers may need to add an
asterisk when using proxies in their override file.

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docs/admin/config/private-network.mdx

@@ -44,6 +44,15 @@ executor|frontend|gitserver|migrator|repo-updater|worker:
     value: "blobstore,codeinsights-db,codeintel-db,sourcegraph-frontend-internal,sourcegraph-frontend,github-proxy,gitserver,grafana,indexed-search-indexer,indexed-search,jaeger-query,pgsql,precise-code-intel-worker,prometheus,redis-cache,redis-store,repo-updater,searcher,symbols,syntect-server,worker-executors,worker,cloud-sql-proxy,localhost,127.0.0.1,.svc,.svc.cluster.local,kubernetes.default.svc"
 ```
 
+<Callout type="info">
+After setting up your proxy in the override file, you may notice some pods like the frontend, gitserver and repo-updater failing health checks. In such a case, you'll need to add an '*' to the NO_PROXY environment variable. This should look like:
+</Callout>
+
+```
+- name: NO_PROXY
+    value: "blobstore,codeinsights-db,codeintel-db,sourcegraph-frontend-internal,sourcegraph-frontend,github-proxy,gitserver,grafana,indexed-search-indexer,indexed-search,jaeger-query,pgsql,precise-code-intel-worker,prometheus,redis-cache,redis-store,repo-updater,searcher,symbols,syntect-server,worker-executors,worker,cloud-sql-proxy,localhost,127.0.0.1,.svc,.svc.cluster.local,kubernetes.default.svc, *"
+```
+
 ### Docker Compose
 
 Add the proxy environment variables your docker compose override file.