doc: fix typographical error

Insert missing word.

PR-URL: #30735
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: Trott

doc/api/perf_hooks.md

@@ -547,7 +547,7 @@ The standard deviation of the recorded event loop delays.
 ### Measuring the duration of async operations
 
 The following example uses the [Async Hooks][] and Performance APIs to measure
-the actual duration of a Timeout operation (including the amount of time it
+the actual duration of a Timeout operation (including the amount of time it took
 to execute the callback).
 
 ```js