doc: remove empty line in YAML block

PR-URL: #44617
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Daeyeon Jeong <daeyeon.dev@gmail.com>
Reviewed-By: Richard Lau <rlau@redhat.com>

Author: ovflowd

Diff for: doc/api/process.md

@@ -3634,7 +3634,6 @@ changes:
     - v12.19.0
     pr-url: https://github.com/nodejs/node/pull/32499
     description: Calling `process.umask()` with no arguments is deprecated.
-
 -->
 
 > Stability: 0 - Deprecated. Calling `process.umask()` with no argument causes