[gatsby-transformer-yaml] Update docs: GraphQL query mismatch (#5402)
[gatsby-transformer-yaml] Update docs: GraphQL query mismatch (#5402)

GraphQL query references "value" when it should actually reference "character" as per the example output.
mingaldrichgan/gatsby,ChristopherBiscardi/gatsby,mingaldrichgan/gatsby,ChristopherBiscardi/gatsby,ChristopherBiscardi/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,mingaldrichgan/gatsby,0x80/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,gatsbyjs/gatsby,fk/gatsby,0x80/gatsby,fk/gatsby,fk/gatsby,ChristopherBiscardi/gatsby,0x80/gatsby,gatsbyjs/gatsby