Update dependency grunt to v1.5.2

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
grunt (source)	1.5.1 -> 1.5.2

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Release Notes

gruntjs/grunt

### [`v1.5.2`](https://togithub.com/gruntjs/grunt/releases/v1.5.2) [Compare Source](https://togithub.com/gruntjs/grunt/compare/v1.5.1...v1.5.2) - Update Changelog [`7f15fd5`](https://togithub.com/gruntjs/grunt/commit/7f15fd5) - Merge pull request [#​1743](https://togithub.com/gruntjs/grunt/issues/1743) from gruntjs/cleanup-link [`b0ec6e1`](https://togithub.com/gruntjs/grunt/commit/b0ec6e1) - Clean up link handling [`433f91b`](https://togithub.com/gruntjs/grunt/commit/433f91b)

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Configuration

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