ReadMe: Replace BlueJeans with UberConference

BlueJeans requires a moderator while UberConference does not

Signed-off-by: Rob Dolin <[email protected]>

Author: RobDolinMS

README.md

@@ -67,7 +67,7 @@ When in doubt, start on the [mailing-list](#mailing-list).
 ## Weekly Call
 
 The contributors and maintainers of the project have a weekly meeting Wednesdays at 10:00 AM PST.
-Everyone is welcome to participate in the [BlueJeans call][BlueJeans].
+Everyone is welcome to participate via [UberConference web][UberConference] or audio-only: 646-494-8704 (no PIN needed.)
 An initial agenda will be posted to the [mailing list](#mailing-list) earlier in the week, and everyone is welcome to propose additional topics or suggest other agenda alterations there.
 Minutes are posted to the [mailing list](#mailing-list) and minutes from past calls are archived to the [wiki](https://github.com/opencontainers/specs/wiki) for those who are unable to join the call.
 
@@ -155,3 +155,4 @@ Read more on [How to Write a Git Commit Message](http://chris.beams.io/posts/git
 8. When possible, one keyword to scope the change in the subject (i.e. "README: ...", "runtime: ...")
 
 [BlueJeans]: https://bluejeans.com/1771332256/
+[UberConference]: https://www.uberconference.com/ssaul