remove 411 (#3516)

- unmaintained since 2019
- no recent activity in issues
- homepage is down
- ref. https://github.com/awesome-selfhosted/awesome-selfhosted/issues/2266

README.md

@@ -1279,7 +1279,6 @@ _See also: [List of streaming media systems - Wikipedia](https://en.wikipedia.or
 Software that does not fit in another section.
 
 - [2FAuth](https://github.com/Bubka/2FAuth) - A web app to manage your Two-Factor Authentication (2FA) accounts and generate their security codes. ([Demo](https://demo.2fauth.app/)) `AGPL-3.0` `PHP`
-- [411](https://github.com/etsy/411) - Alert Management Web Application. `MIT` `PHP`
 - [AlertHub](https://github.com/Ardakilic/alerthub) `⚠` - AlertHub is a simple tool to get alerted from GitHub releases. `MIT` `Nodejs`
 - [Anchr](https://anchr.io) - Anchr is a toolbox for tiny tasks on the internet, including bookmark collections, URL shortening and (encrypted) image uploads. ([Source Code](https://github.com/muety/anchr)) `GPL-3.0` `Nodejs`
 - [Apache Solr](https://lucene.apache.org/solr/) - Solr is the popular, blazing-fast, open source enterprise search platform built on Apache Lucene. ([Source Code](https://lucene.apache.org/solr/downloads.html)) `Apache-2.0` `Java`