Merge branch 'manifest' into 'develop'

Expose /manifest.json for PWA

Closes #882

See merge request pleroma/pleroma!3544

diff --cc lib/pleroma/web/router.ex
Simple merge

diff --cc test/pleroma/web/plugs/frontend_static_plug_test.exs
index 45cd70a2c32cf80f8b6932cd18e08e1f773139b2,031f7a69d788469ef1205f65dc8c431514fec5ab..52379b86a6d3355cb0076afb47228afc198bde74
--- 1/test/pleroma/web/plugs/frontend_static_plug_test.exs
--- 2/test/pleroma/web/plugs/frontend_static_plug_test.exs
+++ b/test/pleroma/web/plugs/frontend_static_plug_test.exs
@@@ -94,9 -94,9 +94,10 @@@ defmodule Pleroma.Web.Plugs.FrontendSta
        "internal",
        ".well-known",
        "nodeinfo",
+       "manifest.json",
        "auth",
        "proxy",
 +      "phoenix",
        "test",
        "user_exists",
        "check_password"