Update soapbox base url

At some point 'soapbox-pub/soapbox-fe' was moved to 'soapbox-pub/soapbox' and the build url is now updated.

config/config.exs

@@ -753,9 +753,9 @@ config :pleroma, :frontends,
     },
     "soapbox-fe" => %{
       "name" => "soapbox-fe",
-      "git" => "https://gitlab.com/soapbox-pub/soapbox-fe",
+      "git" => "https://gitlab.com/soapbox-pub/soapbox",
       "build_url" =>
-        "https://gitlab.com/soapbox-pub/soapbox-fe/-/jobs/artifacts/${ref}/download?job=build-production",
+        "https://gitlab.com/soapbox-pub/soapbox/-/jobs/artifacts/${ref}/download?job=build-production",
       "ref" => "v2.0.0",
       "build_dir" => "static"
     },