Update Clock.js

Remove redundant THREE namespace.

src/core/Clock.js

@@ -58,7 +58,7 @@ class Clock {
 		 */
 		this.running = false;
 
-		warn( 'THREE.Clock: This module has been deprecated. Please use THREE.Timer instead.' ); // @deprecated, r183
+		warn( 'Clock: This module has been deprecated. Please use THREE.Timer instead.' ); // @deprecated, r183
 
 	}