Update community meetings information (#4732)

* Update community meetings information

Signed-off-by: Alvin Lin <alvinlin@amazon.com>

Author: alvinlin123

README.md

@@ -134,7 +134,11 @@ For security issues see https://github.com/cortexproject/cortex/security/policy
 
 The Cortex community call happens every two weeks on Thursday, alternating at 1200 UTC and 1700 UTC. Meeting notes are held [here](https://docs.google.com/document/d/1shtXSAqp3t7fiC-9uZcKkq3mgwsItAJlH6YW6x1joZo/edit).
 
- To get a calendar invite join the [google groups](https://groups.google.com/forum/#!forum/cortex-monitoring) to ask for one.
+To see meeting calendar:
+
+- See the calendar [in your browser (time zone will be UTC)](https://calendar.google.com/calendar/u/0/embed?src=cncf-cortex-maintainers@lists.cncf.io&ctz=UTC).
+- If you use Google Calendar, [add the Cortex's calendar to your own Google Calendar](https://calendar.google.com/calendar/u/0?cid=Y25jZi1jb3J0ZXgtbWFpbnRhaW5lcnNAbGlzdHMuY25jZi5pbw).
+- You can also just [download the .ics file](https://calendar.google.com/calendar/ical/cncf-cortex-maintainers%40lists.cncf.io/public/basic.ics).
 
 ## Hosted Cortex (Prometheus as a service)
 

docs/contributing/how-to-add-a-maintainer.md

@@ -14,6 +14,7 @@ New maintainers are proposed by an existing maintainer and are elected by [major
 1. Invite to [Docker Hub organization](https://hub.docker.com/u/cortexproject)
 1. Submit a PR to [CNCF maintainer list for Cortex](http://maintainers.cncf.io)
 1. Invite to [CNCF `cncf-cortex-maintainers` mailing list](https://lists.cncf.io/g/cncf-cortex-maintainers) (via [CNCF Service Desk](https://servicedesk.cncf.io))
+1. Invite to [Cortex Project Public Calendar](https://calendar.google.com/calendar/u/0?cid=Y25jZi1jb3J0ZXgtbWFpbnRhaW5lcnNAbGlzdHMuY25jZi5pbw)
 1. Invite to [maintainer's Google Docs](https://drive.google.com/drive/folders/1aT7-rx4hvYoB3EjvOeX1LHJhgH0Sawzb)
 1. Add to the Google Analytics property used for the website statistics
 1. Invite to credentials vault