Hang created EnvironmentSchemas off of pipeline definition
During the normal course of execution we were creating the EnvironmentSchema
twice. This solves this systematically (e.g. will be cached in between invocations
Test Plan: BK. See attached screenshots.
Reviewers: max, alangenfeld
Reviewed By: alangenfeld
Differential Revision: https://dagster.phacility.com/D1529