ResolutionMediaFeatureEnabled preference is a no-op

https://bugs.webkit.org/show_bug.cgi?id=255447
rdar://108363296

Reviewed by Brent Fulgham.

> Since bug 248619 removed the (already dead) legacy media queries code, the ResolutionMediaFeatureEnabled setting has had no references within WebKit.
> While dropping this setting is probably fine, we shouldn't have the setting hang around while it does nothing.

* Source/WTF/Scripts/Preferences/UnifiedWebPreferences.yaml:

Canonical link: https://commits.webkit.org/263519@main

Source/WTF/Scripts/Preferences/UnifiedWebPreferences.yaml

@@ -5245,20 +5245,6 @@ ResizeObserverEnabled:
     WebCore:
       default: true
 
-ResolutionMediaFeatureEnabled:
-  type: bool
-  status: stable
-  category: media
-  humanReadableName: "Resolution media feature"
-  humanReadableDescription: "Enable resolution media feature support"
-  defaultValue:
-    WebKitLegacy:
-      default: true
-    WebKit:
-      default: true
-    WebCore:
-      default: true
-
 ResourceLoadSchedulingEnabled:
   type: bool
   status: internal