[mediaqueries-5] Phrasing tweak

See w3c@a2f6a35#r48157340

Author: frivoal

mediaqueries-5/Overview.bs

@@ -2775,7 +2775,7 @@ Detecting Forced Colors Mode: the 'forced-colors' feature</h3>
 		The reduced palette enforced by [=forced colors mode=]
 		can call for some visual simplification of the page.
 		''@media (forced-colors) or (prefers-contrast) { … }''
-		can thus be a useful query to conditionally apply styles that reduce visual clutter,
+		could thus be a useful query to conditionally apply styles that reduce visual clutter,
 		catching all users of forced colors and all users with contrast preferences.
 		''@media (prefers-contrast) { … }'' would leave out forced-colors users
 		with a color scheme that is neither particularly high nor low contrast,