fix compile warnings

lib/mix/tasks/pleroma/common.ex

lib/mix/tasks/pleroma/instance.ex

lib/mix/tasks/pleroma/relay.ex

lib/mix/tasks/pleroma/uploads.ex

lib/mix/tasks/pleroma/user.ex

lib/pleroma/application.ex

lib/pleroma/emoji.ex

lib/pleroma/filter.ex

lib/pleroma/html.ex

lib/pleroma/http/connection.ex

lib/pleroma/list.ex

lib/pleroma/mime.ex

lib/pleroma/notification.ex

lib/pleroma/plugs/authentication_plug.ex

lib/pleroma/plugs/basic_auth_decoder_plug.ex

lib/pleroma/plugs/federating_plug.ex

lib/pleroma/plugs/http_security_plug.ex

lib/pleroma/plugs/session_authentication_plug.ex

lib/pleroma/plugs/uploaded_media.ex

lib/pleroma/plugs/user_fetcher_plug.ex