Let Sentry DSN through CSP

lib/pleroma/web/plugs/http_security_plug.ex

@@ -91,6 +91,7 @@ defp csp_string do
     static_url = Pleroma.Web.Endpoint.static_url()
     websocket_url = Pleroma.Web.Endpoint.websocket_url()
     report_uri = Config.get([:http_security, :report_uri])
+    sentry_dsn = Config.get([:frontend_configurations, :soapbox_fe, "sentryDsn"])
 
     img_src = "img-src 'self' data: blob:"
     media_src = "media-src 'self'"
@@ -122,6 +123,13 @@ defp csp_string do
         connect_src
       end
 
+    connect_src =
+      if sentry_dsn do
+        [connect_src, " ", build_csp_param(sentry_dsn)]
+      else
+        connect_src
+      end
+
     script_src =
       if Config.get(:env) == :dev do
         "script-src 'self' 'unsafe-eval'"