Fix orphaned PR env scan when no non-default workspaces

[lorenyu]

Ticket

Resolves #{TICKET NUMBER OR URL}

Changes

• Add "or true" to grep command that searches for non-default workspaces

Context for reviewers

The Scan orphaned PR environments workflow was failing (Most recent failed run: https://github.com/navapbc/pfml-starter-kit-app/actions/runs/13625676007)

When there's only one workspace, terraform workspace list will return * default, which doesn't get found by grep -o 'p-[0-9]\+' which is only looking for lines without the *. This means that the grep returns a status code of 1, causing the line workspaces="$(terraform -chdir="infra/${app_name}/service" workspace list)" to fail, terminating the script.

This change fixes this issue by adding || true to the grep part of the command pipeline.

Testing

see https://github.com/navapbc/pfml-starter-kit-app/pull/266

[lorenyu]

duplicate of #889