Update unit test naming guidelines

[NicolasMassart]

Test Naming Guidelines Update

Updates our test naming conventions to improve clarity and maintainability of our test suite.

Key Changes

• Established clear guidelines for naming unit tests
• Added examples of good and bad practices
• Introduced principles for more descriptive and concise test names

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Note

Overhauls unit testing guidelines with clearer naming conventions, scenario grouping, isolation practices, and snapshot usage, adding concise rules and expanded examples.

• Docs: docs/testing/unit-testing.md
  • Naming & Structure:
    • Clarifies describe usage (by function and scenario) and it descriptions with action-oriented, behavior-focused phrasing; de-emphasizes “should”.
    • Adds comprehensive examples contrasting good vs. bad test names and scopes; avoids redundancy and implementation details.
  • Test Focus & Private Code:
    • Reinforces single-behavior tests and testing via public interfaces (not private methods), with illustrative examples.
  • Test Phases & Readability:
    • Highlights setup/exercise/verify/teardown phases and spacing to improve readability, with before/after examples.
  • Isolation Practices:
    • Advises resetting mocks (resetMocks, restoreMocks), handling globals via spies/wrappers/DI, and replacing shared vars with factories.
    • Recommends avoiding beforeEach in favor of setup helpers/wrappers; includes teardown pattern.
  • Mocks & Snapshots:
    • Prefers Jest mocks over Sinon; cautions on general manual mocks.
    • Refines snapshot test naming to reflect “matches rendered snapshot” and clarifies snapshot limitations.

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[Copilot]

Pull Request Overview

This PR updates our unit test naming guidelines to improve clarity and maintainability of our test suite.

• Added a structured set of instructions for naming tests using active verbs.
• Included new examples of both poor ("Don't") and good ("Do") naming practices.
• Provided an extended list of considerations to ensure test names are descriptive and concise.

Comments suppressed due to low confidence (1)

docs/testing/unit-testing.md:125

• [nitpick] The test name in this example includes the 'should' prefix even though the guidelines recommend avoiding it. Consider revising the test name to remove the 'should' prefix and focus directly on the behavior.

it('should successfully add token when address is valid and decimals are set and symbol exists', () => {