[Snyk] Security upgrade gatsby-plugin-sharp from 2.0.20 to 2.6.18

[adamlaska]

This PR was automatically created by Snyk using the credentials of a real user.


Snyk has created this PR to fix 1 vulnerabilities in the npm dependencies of this project.

Snyk changed the following file(s):

• website/package.json

Vulnerabilities that will be fixed with an upgrade:

	Issue	Score
	Heap-based Buffer Overflow SNYK-JS-CWEBPBIN-5923346	909

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• This PR was automatically created by Snyk using the credentials of a real user.

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