chore(deps): update gatsby monorepo

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
babel-preset-gatsby	devDependencies	patch	0.5.13 -> 0.5.14
gatsby (changelog)	dependencies	patch	2.24.73 -> 2.24.77
gatsby-plugin-netlify	dependencies	patch	2.3.17 -> 2.3.18
gatsby-plugin-sharp	dependencies	patch	2.6.40 -> 2.6.42
gatsby-source-contentful	dependencies	patch	2.3.51 -> 2.3.52
gatsby-transformer-remark	dependencies	patch	2.8.38 -> 2.8.39

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Release Notes

gatsbyjs/gatsby

### [`v0.5.14`](https://togithub.com/gatsbyjs/gatsby/compare/84fa4be59108d02c40acbd2fb07c96a0c85aa85c...e2605d79f3815c31c1c3458e48d15dc23256f4bd) [Compare Source](https://togithub.com/gatsbyjs/gatsby/compare/84fa4be59108d02c40acbd2fb07c96a0c85aa85c...e2605d79f3815c31c1c3458e48d15dc23256f4bd)

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