Add alert list empty state for those with reporter access
Problem to solve
Alerts can contain sensitive information about business critical systems. This information is frequently protected and available only to those who are responsible for maintaining the systems so that business services cannot be disrupted either intentionally or on accident. Alerts need to be restricted to certain roles within GitLab so that users have the ability to protect critical information via role assignment. For this reason, users with reporter-level access do not have permissions to either set up or view alerts. To reduce confusion, we are replacing the current 404 message with an informative message explaining why they cannot view alerts.
Intended users
Further details
This work drives the direction of the Alert Management category.
Proposal
As discussed in &2877 (comment 340317719), have the same empty state we use for those with other permissions levels, but update the text to correspond to actions that those with reporter-level access could take to enable alert management. The text would be updated to read:
Display alerts from all your monitoring tools directly within GitLab. Streamline the investigation of your alerts and the promotion of alerts to incidents. Contact an admin to enable this feature.