fix(perforce): Add IP allowlisting guidance to Perforce docs (#16850)

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Author: mujacica

docs/organization/integrations/source-code-mgmt/perforce/index.mdx

@@ -35,7 +35,7 @@ Before installing, make sure you have:
 - **Sentry permissions**: Organization owner, manager, or admin role.
 - **Perforce server access**: A Perforce user account with read access to the depots you want to connect. We recommend creating a dedicated service account (e.g., `sentry-bot`).
 - **SSL fingerprint** (if using SSL): Obtain it by running `p4 -p ssl:<host>:<port> trust -y` on a machine with access to your Perforce server.
-- **Network connectivity**: The Sentry application must be able to reach your Perforce server over the network on the configured port.
+- **Network connectivity**: The Sentry application must be able to reach your Perforce server over the network on the configured port. Make sure the [IP addresses Sentry uses to make outbound requests](/security-legal-pii/security/ip-ranges/) are allowed by your firewall or network configuration.
 
 <Alert title="Note">
 
@@ -162,6 +162,7 @@ The following features are **not supported** by the Perforce integration:
 If you see "Failed to connect to Perforce server", verify:
 
 - Your P4PORT address is correct and reachable from Sentry's network.
+- The [IP addresses Sentry uses to make outbound requests](/security-legal-pii/security/ip-ranges/) are allowed by your firewall or network configuration.
 - If using SSL, ensure the SSL fingerprint is correct. Re-obtain it with: `p4 -p ssl:<host>:<port> trust -y`
 - Your firewall allows inbound connections on the Perforce port (typically 1666).