Updates to the Build Config - Taskgraph submodule

[Andrew Halberstadt]

Hi everyone,

The Core: Build Config - Taskgraph submodule is quite out of date, with the owner and most of the peers no longer active with the project (or Mozilla). I'd like to propose Tom Prince, Aki Sasaki, Brian Stack, Gregory Szorc and Justin Wood be moved to owner/peers emeritus.

In their place, I propose I step up from a peer to take over ownership of this submodule, and that we add Johan Lorenzo and Julien Cristau as new peers. Johan, Julien and I are all very active in the Taskgraph project, have a deep technical understanding of how it works, and are each quite familiar with various aspects of Gecko's CI configuration.

Barring any objections, I'd like to land the following revision to update the module next week:

https://phabricator.services.mozilla.com/D163752

Please let me know if you have any suggestions or concerns!

Andrew