Enable Jest ESLint plugin with recommended config

[alexeyr-ci2]

Summary

Include the Jest ESLint plugin and fix the tests accordingly.

Pull Request checklist

• Add/update test to cover these changes
• [ ] Update documentation
• [ ] Update CHANGELOG file

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This change is 

Summary by CodeRabbit

• New Features
  • Enhanced the linting configuration to better integrate with Jest testing framework.
• Tests
  • Streamlined assertions and removed unnecessary assertion counts for improved test clarity and consistency.
  • Reorganized test suites to ensure a cleaner and more isolated testing environment.
• Chores
  • Upgraded development dependencies, including the addition of eslint-plugin-jest and an update to typescript-eslint.
  • Adjusted script handling for package.json dependencies.

[coderabbitai]

Walkthrough

A new Jest-specific configuration has been added to the ESLint settings to better support test files. The changes include importing the Jest plugin and adding a configuration block that applies to files matching Jest test patterns. In several test files, assertion methods have been updated from toEqual to toBe, and explicit expect.assertions calls have been removed. Some tests also saw improvements in error handling and organization. The package dependencies have been updated accordingly.

Changes

Files	Summary of Changes
eslint.config.ts	Added a Jest-specific configuration block with file patterns, imported eslint-plugin-jest, extended Jest’s recommended configurations, and removed legacy Mocha/Jest globals.
node_package/tests/Authenticity.test.js, node_package/tests/ReactOnRails.test.jsx, node_package/tests/serverRenderReactComponent.test.ts	Changed assertions from toEqual to toBe for function type and string/HTML equality checks.
node_package/tests/Authenticity.test.js, node_package/tests/ReactOnRails.test.jsx, node_package/tests/renderFunction.test.jsx, node_package/tests/scriptSanitizedVal.test.js, node_package/tests/buildConsoleReplay.test.js	Removed explicit expect.assertions calls to streamline tests.
node_package/tests/ComponentRegistry.test.js	Refactored error handling by declaring an error variable outside the catch block and moving the assertion to check the error message after the catch.
node_package/tests/StoreRegistry.test.js, node_package/tests/buildConsoleReplay.test.js	Improved test organization by adding a beforeEach hook for state cleanup and updating suite/test descriptions for clarity.
package.json	Added "eslint-plugin-jest": "^28.11.0" as a new dependency and updated "typescript-eslint" from ^8.26.1 to ^8.29.1.
script/convert	Added a line to remove the "eslint-plugin-jest" entry from package.json.

Possibly related PRs

• Update CONTRIBUTING and testing dependencies #1675: Updates in Jest configurations and testing dependencies align with this PR's focus on testing framework enhancements.

Suggested reviewers

• Judahmeek

Poem

I’m a rabbit, hopping with glee,
Configuring tests so sprightly and free.
With Jest in our ESLint, oh what a sight,
Assertions now bouncy and shining bright.
Bugs scurry off as I nibble each byte,
A carrot of code, my pure delight! 🐇
Hop on, let’s code into the night!

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📥 Commits

Reviewing files that changed from the base of the PR and between d687a6f and fc64ba1.

📒 Files selected for processing (1)

• script/convert (1 hunks)

🚧 Files skipped from review as they are similar to previous changes (1)

• script/convert

⏰ Context from checks skipped due to timeout of 90000ms (4)

• GitHub Check: build-dummy-app-webpack-test-bundles (oldest)
• GitHub Check: rspec-package-tests (oldest)
• GitHub Check: build
• GitHub Check: rspec-package-tests (newest)

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[alexeyr-ci2]

Avoids conditional expect (though expect.assertions will catch the problem if there is no error too, we could just disable the rule here instead).

[alexeyr-ci2]

eslint-plugin-jest bans these expect.assertions(...) calls outside actual tests.

The ones in them are allowed but not actually useful, they are good in two cases:

1. testing async logic with callbacks instead of async/await;
2. conditional expect including in try/catch, also banned by the plugin.