Update dependency grunt-contrib-less to v3

[renovate[bot]]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
grunt-contrib-less	2.0.0 -> 3.0.0

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Release Notes

gruntjs/grunt-contrib-less

v3.0.0

Compare Source

v2.1.0

Compare Source

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Configuration

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