chore(showcase): add PicPick to showcase (#13279)
chore(showcase): add PicPick to showcase (#13279)

Added https://picpick.app/ to showcase.

This site has been developed using gatsby since early 2018, but I recently upgraded to v2 with plugin https://github.com/wiziple/gatsby-plugin-intl to support 15 different languages. 😄

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## Description

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## Related Issues

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gatsbyjs/gatsby,ChristopherBiscardi/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,ChristopherBiscardi/gatsby,gatsbyjs/gatsby,ChristopherBiscardi/gatsby,ChristopherBiscardi/gatsby