ci: migrate e2e to eslint v9 flat config

[MikeMcC399]

What's the problem this PR addresses?

• supersedes ci: specify legacy config for e2e eslint #6690

The workflow .github/workflows/e2e-eslint-workflow.yml fails with

Oops! Something went wrong! :(

ESLint: 9.20.1

ESLint couldn't find an eslint.config.(js|mjs|cjs) file.

It was last successful 11 months ago on Apr 5, 2024 coinciding with the release of ESLint 9.0.0 which changed the default config to flat.

The workflow installs eslint with no version specified, therefore eslint@latest is used (currently [email protected]).

How did you fix it?

In the workflow .github/workflows/e2e-eslint-workflow.yml

each .estlintrc is changed to eslint.config.mjs

Validating ESLint

The ESLint rule semi was deprecated in ESLint v8.53.0 and moved instead to @stylistic/eslint-plugin-js.

Following the ESLint Stylistic Migration Guide and using the recommended approach of one single plugin, additionally install @stylistic/eslint-plugin.

Use the rule @stylistic/semi.

Running the TypeScript integration test

typescript-eslint v7 allows switching from @typescript-eslint/parser and @typescript-eslint/eslint-plugin to typescript-eslint.

Checklist

• I have read the Contributing Guide.
• I have set the packages that need to be released for my changes to be effective. (none)
• I will check that all automated PR checks pass before the PR gets reviewed.

[arcanis]

Thanks!