fix(deps): update starters and examples - gatsby

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
gatsby (changelog)	^3.7.2 -> ^3.8.0
gatsby-plugin-feed	^3.7.1 -> ^3.8.0
gatsby-plugin-gatsby-cloud	^2.7.1 -> ^2.8.1
gatsby-plugin-google-analytics	^3.7.1 -> ^3.8.0
gatsby-plugin-image	^1.7.1 -> ^1.8.0
gatsby-plugin-manifest	^3.7.1 -> ^3.8.0
gatsby-plugin-offline	^4.7.1 -> ^4.8.0
gatsby-plugin-react-helmet	^4.7.1 -> ^4.8.0
gatsby-plugin-sharp	^3.7.1 -> ^3.8.0
gatsby-source-filesystem	^3.7.1 -> ^3.8.0
gatsby-transformer-sharp	^3.7.1 -> ^3.8.0

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Release Notes

gatsbyjs/gatsby

v3.8.0

Compare Source

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