Update PR URL in net.md for TCP_KEEPINTVL changes

Author: guybedford

doc/api/net.md

@@ -1386,7 +1386,7 @@ Set the encoding for the socket as a [Readable Stream][]. See
 added: v0.1.92
 changes:
   - version: REPLACEME
-    pr-url: https://github.com/nodejs/node/pull/REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/63825
     description: Added the `interval` and `count` arguments to configure
                  `TCP_KEEPINTVL` and `TCP_KEEPCNT`.
   - version: