[gatsby-plugin-sharp] tests: mock async/queue to not actually run sharp sizing (#5426)
[gatsby-plugin-sharp] tests: mock async/queue to not actually run sharp sizing (#5426)


gatsbyjs/gatsby,ChristopherBiscardi/gatsby,fk/gatsby,fk/gatsby,gatsbyjs/gatsby,fk/gatsby,ChristopherBiscardi/gatsby,mingaldrichgan/gatsby,mingaldrichgan/gatsby,gatsbyjs/gatsby,0x80/gatsby,0x80/gatsby,0x80/gatsby,gatsbyjs/gatsby,mingaldrichgan/gatsby,ChristopherBiscardi/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,ChristopherBiscardi/gatsby