[Snyk] Security upgrade react-scripts from 3.4.0 to 4.0.0

[joeawillis]

Snyk has created this PR to fix 1 vulnerabilities in the yarn dependencies of this project.

Snyk changed the following file(s):

• example/package.json
• example/yarn.lock

Note for zero-installs users

If you are using the Yarn feature zero-installs that was introduced in Yarn V2, note that this PR does not update the .yarn/cache/ directory meaning this code cannot be pulled and immediately developed on as one would expect for a zero-install project - you will need to run yarn to update the contents of the ./yarn/cache directory.
If you are not using zero-install you can ignore this as your flow should likely be unchanged.

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This major version upgrade of react-scripts from 3.4.0 to 4.0.0 introduces significant breaking changes to the build and development environment. Key changes include upgrades to core dependencies like ESLint and Jest, and a new hot-reloading mechanism.

Highlights:

• Dependency Upgrades: ESLint is upgraded to v7 and Jest to v26. [2, 6] This may introduce new linting errors and cause existing tests to fail. Custom ESLint configurations and test suites will likely require updates. [6]
• Fast Refresh: React Hot Loader is replaced by Fast Refresh, which preserves component state during reloads but is a fundamental change to the development server. [1, 6]

Source: Create React App GitHub Releases
Recommendation: Before merging, review and update any custom ESLint rules and validate all tests against the new Jest version. For TypeScript projects, you may need to regenerate the tsconfig.json file. [4, 7]

Notice 🤖: This content was generated using artificial intelligence. AI-generated content may contain errors and should be reviewed for accuracy before use.

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Vulnerabilities that will be fixed with an upgrade:

	Issue	Score
	Prototype Pollution SNYK-JS-JSYAML-13961110	631

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Important

• Check the changes in this PR to ensure they won't cause issues with your project.
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🦉 Prototype Pollution