chore(deps): update dependency sinon to v2.4.1

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
sinon (source)	2.3.5 -> 2.4.1

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Release Notes

sinonjs/sinon (sinon)

### [`v2.4.1`](https://togithub.com/sinonjs/sinon/blob/HEAD/CHANGES.md#241) [Compare Source](https://togithub.com/sinonjs/sinon/compare/v2.4.0...v2.4.1) - stub#withArgs: set promiseLibrary correctly ([#​1497](https://togithub.com/sinonjs/sinon/issues/1497)) ### [`v2.4.0`](https://togithub.com/sinonjs/sinon/blob/HEAD/CHANGES.md#240) [Compare Source](https://togithub.com/sinonjs/sinon/compare/v2.3.8...v2.4.0) - Allow anonymous mock functions to be named ### [`v2.3.8`](https://togithub.com/sinonjs/sinon/blob/HEAD/CHANGES.md#238) [Compare Source](https://togithub.com/sinonjs/sinon/compare/v2.3.7...v2.3.8) - Fix 1474: propagates promiseLibrary to new stub behaviors ([#​1484](https://togithub.com/sinonjs/sinon/issues/1484)) ### [`v2.3.7`](https://togithub.com/sinonjs/sinon/blob/HEAD/CHANGES.md#237) [Compare Source](https://togithub.com/sinonjs/sinon/compare/v2.3.6...v2.3.7) - Fix [#​1476](https://togithub.com/sinonjs/sinon/issues/1476): spy.withArgs(args...).firstCall is broken ### [`v2.3.6`](https://togithub.com/sinonjs/sinon/blob/HEAD/CHANGES.md#236) [Compare Source](https://togithub.com/sinonjs/sinon/compare/v2.3.5...v2.3.6) - Fix [#​1274](https://togithub.com/sinonjs/sinon/issues/1274): spy.withArgs(args...).callCount is incorrect

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