Update APK link for final release.

apk.html

@@ -60,7 +60,7 @@
 
           <img src="img/apk/unknown-sources-cropped.png">
 
-          <p>3) Open the web browser and go to <a href="https://briarproject.org">https://briarproject.org</a>. Then go to <a href="https://briarproject.org/rc/briar.apk">https://briarproject.org/rc/briar.apk</a>.</p>
+          <p>3) Open the web browser and go to <a href="https://briarproject.org">https://briarproject.org</a>. Then go to <a href="https://briarproject.org/apk/briar.apk">https://briarproject.org/apk/briar.apk</a>.</p>
 
           <p>4) Confirm that you want to download the file.</p>