Update dependency gzip-size to v6

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
gzip-size	devDependencies	major	^5.1.1 -> ^6.0.0

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Release Notes

sindresorhus/gzip-size

v6.0.0

Compare Source

Breaking

• Require Node.js 10 (#​20) 211169f

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Renovate configuration

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[github-actions]

Size Change: 0 B

Total Size: 7.48 kB

ℹ️ View Unchanged

Filename	Size	Change
dist/currency.es.js	2.07 kB	0 B
dist/currency.js	2.08 kB	0 B
dist/currency.min.js	1.14 kB	0 B
dist/currency.umd.js	2.2 kB	0 B

_{compressed-size-action}

[coveralls]

Coverage remained the same at 100.0% when pulling 186a4c5 on renovate/gzip-size-6.x into 7047aae on master.