chore(deps): Bump webpack, gatsby, gatsby-plugin-manifest, gatsby-plugin-offline, gatsby-plugin-react-helmet, gatsby-plugin-sass, gatsby-source-filesystem and gatsby-transformer-sharp

chore(deps): Bump webpack, gatsby, gatsby-plugin-manifest, gatsby-plugin-offline, gatsby-plugin-react-helmet, gatsby-plugin-sass, gatsby-source-filesystem and gatsby-transformer-sharp #12