fix(deps): update starters and examples - gatsby

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
gatsby (changelog)	^3.11.1 -> ^3.12.1
gatsby-plugin-feed	^3.11.0 -> ^3.12.0
gatsby-plugin-google-analytics	^3.11.0 -> ^3.12.0
gatsby-plugin-image	^1.11.0 -> ^1.12.0
gatsby-plugin-manifest	^3.11.0 -> ^3.12.0
gatsby-plugin-offline	^4.11.0 -> ^4.12.0
gatsby-plugin-react-helmet	^4.11.0 -> ^4.12.0
gatsby-plugin-sharp	^3.11.0 -> ^3.12.0
gatsby-remark-copy-linked-files	^4.8.0 -> ^4.9.0
gatsby-remark-images	^5.8.0 -> ^5.9.0
gatsby-remark-prismjs	^5.8.0 -> ^5.9.0
gatsby-remark-responsive-iframe	^4.8.0 -> ^4.9.0
gatsby-remark-smartypants	^4.8.0 -> ^4.9.0
gatsby-source-filesystem	^3.11.0 -> ^3.12.0
gatsby-transformer-remark	^4.8.0 -> ^4.9.0
gatsby-transformer-sharp	^3.11.0 -> ^3.12.0

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Release Notes

gatsbyjs/gatsby

v3.12.1

Compare Source

v3.12.0

Compare Source

Note: Version bump only for package gatsby-plugin-google-analytics

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