batches: disable chromatic snapshot checking for `ExecutionWorkspaces`

Created by: courier-new

This storybook story was not intended to be checked by Chromatic and was causing flakes as a result. While Adam fixed the flakes by providing more mock query data (‍♀️), I still wanted to disable the snapshots. I considered reverting the mock query changes since they aren't integral to the story, but they're fairly unintrusive and harmless, and the storybook stories probably look better with them anyway.

Test plan

Just changes the Chromatic configuration for a component storybook story.

App preview:

• Web
• Storybook

Check out the client app preview documentation to learn more.