Convert prevent_blocking_non_deployment_jobs feature flag into group/project setting

Everyone can contribute. Help move this issue forward while earning points, leveling up and collecting rewards.

• Close this issue

Problem to solve

Fixing the bug described in #390025 (closed) introduces a breaking change for users that have built their workflows around the old behaviour.

Currently the fix is behind a feature flag, prevent_blocking_non_deployment_jobs, which has not yet been rolled out (though it has been enabled for several individual projects on request).

Proposal

Add a new configuration option at the project and group level that toggles this behaviour instead of using a feature flag. If set at a higher level in a hierarchy, lower levels should inherit the value (a Cascading Setting).

Intended users

Feature Usage Metrics

Does this feature require an audit event?