refactor(js): assign LogtoError code to message

[IceHe]

Summary

refactor(js): assign LogtoError code to message too

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Problem:

  test('callback uri, without code, should throw', () => {
    ……
    expect(() => ……).toThrowError(new LogtoError('callbackUri.missingCode'));
  });

is as same as

  test('callback uri, without code, should throw', () => {
    ……
    expect(() => ……).toThrowError();
  });

because

/**
 * If you want to test that a specific error is thrown inside a function.
 */
toThrowError(error?: string | Constructable | RegExp | Error): R;

toThrowError can only check the properties (e.g. message) defined in Error,
and cannot check the properties (e.g. code) defined in classes extends from Error.

My solution is to assign the property LogtoError.code to its parent class property Error.message
so that toThrowError can assert the content of LogtoError.code.

Linear Issue Reference

Related #127 #131 LOG-1355 LOG1356

Testing

Pass all existing unit tests.

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@logto-io/eng

[gao-sun]

You can use jest-matcher-specific-error https://github.com/logto-io/logto/blob/master/packages/core/src/database/insert-into.test.ts

[IceHe]

Follow the best practice.