Draft: Catch and return message for status page AWS error

What does this MR do and why?

Handles client errors like Aws::S3::Errors::InvalidAccessKeyId when publishing content to Status Page, so the error gets appropriately logged (rather than contributing to grouprespond's error budget).

How to set up and validate locally

1. With developer+ permissions, create an incident issue
   • Monitor > Incidents > Create incident (UI) or via rails console
2. Find the incident in the console

   incident = Issue.incident.last

3. Set up a faux Status Page setting
   • In the rails console, run:

     ::StatusPage::ProjectSetting.create!(
       project_id: incident.project_id, 
       enabled: true,
       aws_s3_bucket_name: "bucket-name",
       aws_region: "us-east-1",
       aws_access_key: "FFFFFFFFFFFFFFFFFFFF",
       aws_secret_key: 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa',
       status_page_url: "https://status.gitlab.com"
     )

   • we validate the bucket details on save, but users could always delete the AWS S3 bucket later & we wouldn't know to invalidate the record on our side. Creating a valid record with no real corresponding S3 bucket mimics that scenario.
4. Run the worker for the incident/project & your user
   • Run:

     ::StatusPage::PublishWorker.new.perform(User.first, incident.project_id, incident.id)

   • If you have issues with IncidentCounter load errors, run load 'ee/lib/gitlab/status_page/usage_data_counters/incident_counter.rb' in the console before running the worker. I double-checked, and we are still recording usage data for publishing/unpublishing incidents, so I'm not entirely sure what's going on with that. But it's the only usage data counter which isn't in GitLab::UsageDataCounters module, so I'm guessing it's something to do with that/load order/etc.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.