Fix beta builds

The extension's beta name strings were missing.

Change-Id: I0245671c627aced507a9c6460bd6b852aaf1ebaa
diff --git a/src/_locales/de/messages.json b/src/_locales/de/messages.json
index 59fe3be..b45e357 100644
--- a/src/_locales/de/messages.json
+++ b/src/_locales/de/messages.json
@@ -53,6 +53,9 @@
    "name": {

       "message": "Bildschirmerfassung"

    },

+   "name_beta": {

+      "message": "Bildschirmerfassung (beta)"

+   },

    "ok": {

       "message": "OK"

    },