supressing → suppressing (#4496)

I've got a strange case of deja vu about this, but can't find an earlier
PR with it in, so…

Co-authored-by: Patrick H. Lauke <redux@splintered.co.uk>
Co-authored-by: Mike Gower <mikegower@gmail.com>

Author: 3 people

understanding/21/status-messages.html

@@ -22,7 +22,7 @@ <h2>In brief</h2>
 		<section id="intent">
 			<h2>Intent of this Success Criterion</h2>
 			<p>The intent of this success criterion is to make users aware of important changes in content that are not given focus, and to do so in a way that doesn't unnecessarily interrupt their work.</p>
-			<p>The intended beneficiaries are blind and low vision users of assistive technologies with screen reader capabilities. An additional benefit is that assistive technologies for users with cognitive disabilities may achieve an alternative means of indicating (or even delaying or supressing) status messages, as preferred by the user.</p>
+			<p>The intended beneficiaries are blind and low vision users of assistive technologies with screen reader capabilities. An additional benefit is that assistive technologies for users with cognitive disabilities may achieve an alternative means of indicating (or even delaying or suppressing) status messages, as preferred by the user.</p>
 <p>The scope of this success criterion is specific to changes in content that involve status messages. A <a>status message</a> is a defined term in WCAG. There are two main criteria that determine whether something meets the definition of a status message:</p>
 	<ul>
 		<li> the message <q>provides information to the user on the success or results of an action, on the waiting state of an application, on the progress of a process, or on the existence of errors;</q></li>