Fix browser_permissions deployments.md link

docs/browser_permissions.md

@@ -4,7 +4,7 @@ support.mozilla.org has certain elevated permissions in Firefox,
 shown in [the Firefox source code](https://searchfox.org/mozilla-central/source/browser/app/permissions),
 allowing it to control various aspects of Firefox's UI and retrieve debugging information.
 
-Testing this on our [other deployments](deployments) or locally requires extra configuration and setup.
+Testing this on our [other deployments](deployments.md) or locally requires extra configuration and setup.
 
 ## Adding permissions