Update gulp-imagemin to version 2.4.0 🚀

[greenkeeperio-bot]

Hello :wave:

:rocket::rocket::rocket:

gulp-imagemin just published its new version 2.4.0, which is not covered by your current version range.

If this pull request passes your tests you can publish your software with the latest version of gulp-imagemin – otherwise use this branch to work on adaptions and fixes.

Happy fixing and merging :palm_tree:

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The new version differs by 3 commits .

• 7b8a934 2.4.0
• 1b3a032 tweaks
• 0dd4d3a :arrow_up: imagemin@4.0.0

See the full diff.

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