Configure eslint job to output Code Quality report

What does this MR do?

• Add a dependency that allows eslint to create JSON reports that GitLab Code Quality can import.
• Configure the ESLint job to create such a report.

Note: the formatter only creates a report file if it detects that the process is running in CI. (It does this by looking for CI-related env vars.) This means that non-CI-based eslint runs are not affected and do not create such a file.

Verification

The functionality is demonstrated in a separate MR: !168587 (closed). That MR includes breaking a few lint rules to show that the report is successfully generated.

The report can be seen in a few places:

• MR widget:

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• Pipeline report

  • This report can time out with large reports; this is a preexisting issue that is not specific to this particular Code Quality report. It will also be mitigated as we remove CodeClimate-based scanning.

• MR Changes (diff) view:

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Related issues

Dogfood new direction for Code Quality in gitla... (#382153)

This is part of replacing CodeClimate-based scanning with direct usage of scanning tools. Dogfooding this approach will help accelerate the transition for customers.

Documentation will soon include these specific steps: Docs: Add catalog of common tools integrated wi... (!172633 - merged).

Checklist

Pre-merge

Consider the effect of the changes in this merge request on the following:

• Different pipeline types
• Non-canonical projects:
  • gitlab-foss
  • security
  • dev
  • personal forks
• Pipeline performance

If new jobs are added:

• Change-related rules (e.g. frontend/backend/database file changes): _____
• Frequency they are running (MRs, main branch, nightly, bi-hourly): _____
• Add a duration chart to https://app.periscopedata.com/app/gitlab/652085/Engineering-Productivity---Pipeline-Build-Durations if there are new jobs added to merge request pipelines

This will help keep track of expected pipeline time and cost increases.

Post-merge

• Consider communicating these changes to the broader team following the communication guideline for pipeline changes