docs: fix gatsby-source-graphql README links (#8886)
docs: fix gatsby-source-graphql README links (#8886)


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