Add `scans` field to securityReportSummary on GraphQL

What does this MR do?

This MR introduces a new field called scans for the SecurityReportSummarySection GraphQL types. The idea behind this new field is that we will inform the users about the errors that happened during the report ingestion process.

The query to utilize this new field would look like this;

query getScanInfo($projectPath: ID!, $pipelineID: ID!) {
  project(fullPath: $projectPath) {
    pipeline(iid: $pipelineID) {
      securityReportSummary {
        dast {
          vulnerabilitiesCount
          scans {
            nodes {
              name
              errors
            }
          }
        }
      }
    }
  }
}

Related to #321927 (closed).

Does this MR meet the acceptance criteria?

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