chore: gitignore generated next-env types

[riley-kohler]

Pull Request

Proposed Changes

Add next-env.d.ts to the gitignore file since it is autogenerated by next and should not be edited. This came up because next changed a reference link in that file and caused it to appear in the git's changed files.

Readiness Checklist

Author/Contributor

• If documentation is needed for this change, has that been included in this pull request
• run npm run lint and fix any linting issues that have been introduced
• run npm run test and run tests
• If publishing new data to the public (scorecards, security scan results, code quality results, live dashboards, etc.), please request review from @jeffrey-luszcz

Reviewer

• Label as either bug, documentation, enhancement, infrastructure, maintenance, or breaking