doc: remove double line break

This is the only double line break in the file and for
consistency one is removed.

PR-URL: #17581
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ron Korving <ron@ronkorving.nl>

doc/api/deprecations.md

@@ -788,7 +788,6 @@ The AsyncHooks Sensitive API was never documented and had various of minor
 issues, see https://github.com/nodejs/node/issues/15572. Use the `AsyncResource`
 API instead.
 
-
 <a id="DEP0086"></a>
 ### DEP0086: Remove runInAsyncIdScope