.github: Add ec2 information as a step (#63784)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/63784
Also creates the common.yml.j2 file as a place to store common code
amongst the templates
Should look like:
Signed-off-by: Eli Uriegas <eliuriegas@fb.com>
Test Plan: Imported from OSS
Reviewed By: malfet, driazati
Differential Revision: D30490682
Pulled By: seemethere
fbshipit-source-id: 18028b4acff938ef54cd6e4877561b2d830a11cf
