Update plans.mdx (#21397)

* Update plans.mdx

Was missing 1918 after RFC

* Update src/content/docs/magic-firewall/plans.mdx

---------

Co-authored-by: Kody Jackson <[email protected]>

Author: jmanzanoCF

src/content/docs/magic-firewall/plans.mdx

@@ -30,5 +30,5 @@ All standard features are included with the purchase of the advanced features be
 * Block or allow packets based on Autonomous System Number (ASN).
 * Packet captures on demand for network troubleshooting.
 * [Protocol validation rules](/magic-firewall/about/protocol-validation-rules/) to inspect traffic validity and enforce a positive security model.
-* [Secure Web Gateway](/cloudflare-one/policies/gateway/) filtering for outbound Internet traffic (network and HTTP policies). The Secure Web Gateway supports all TCP and UDP ports, as well as traffic sourced from RFC. Gateway will proxy BYOIP traffic to egress via the default Cloudflare IPs or your assigned [dedicated egress IPs](/cloudflare-one/policies/gateway/egress-policies/dedicated-egress-ips/).
+* [Secure Web Gateway](/cloudflare-one/policies/gateway/) filtering for outbound Internet traffic (network and HTTP policies). The Secure Web Gateway supports all TCP and UDP ports, as well as traffic sourced from RFC 1918 address space. Gateway will proxy BYOIP traffic to egress via the default Cloudflare IPs or your assigned [dedicated egress IPs](/cloudflare-one/policies/gateway/egress-policies/dedicated-egress-ips/).
 * Intrusion Detection System (IDS).