Add GraphQL content in Golang Roadmap (#2265)

* Add GraphQL content in Golang Roadmap

* Add content for gqlgen library

content/roadmaps/109-golang/content/107-go-api-clients/101-graphql/101-gqlgen.md

@@ -1 +1,8 @@
-# Gqlgen
+# Gqlgen
+
+According to their documentation, it's a Golang library for building GraphQL servers without much effort.
+
+<ResourceGroupTitle>Free Content</ResourceGroupTitle>
+<BadgeLink colorScheme='blue' badgeText='Official Website' href='https://gqlgen.com/'>Gqlgen website documentation</BadgeLink>
+<BadgeLink badgeText='Read' href='https://99designs.com.au/blog/engineering/gqlgen-a-graphql-server-generator-for-go/'>Introducing gqlgen: a GraphQL Server Generator for Go</BadgeLink>
+<BadgeLink badgeText='Watch' colorScheme="red" href='https://www.youtube.com/watch?v=O6jYy421tGw'>GraphQL in Go - GQLGen Tutorial (by acklackl on YouTube)</BadgeLink>

content/roadmaps/109-golang/content/107-go-api-clients/101-graphql/readme.md

@@ -1 +1,16 @@
-# Graphql
+# Graphql
+
+`GraphQL` is a query language for [APIs](https://developer.mozilla.org/en-US/docs/Glossary/API), it offers a service that prioritizes giving just the data that the client requested and no more.
+
+Besides, you don't need to be worried about breaking changes, versioning and backwards compatibility like REST APIs. Therefore you can implement your version and auto-document your API just by using `GraphQL`.
+
+<ResourceGroupTitle>Free Content</ResourceGroupTitle>
+
+<BadgeLink colorScheme='blue' badgeText='Official Website' href='https://graphql.org/'>GraphQL Website</BadgeLink>
+<BadgeLink badgeText='Read' href='https://graphql.org/learn/'>Learn GraphQL</BadgeLink>
+<BadgeLink badgeText='Read' href='https://www.graphql.com/tutorials/'>GraphQL Tutorials</BadgeLink>
+<BadgeLink badgeText='Read' href='https://www.redhat.com/en/topics/api/what-is-graphql'>Red Hat: What is GraphQL?</BadgeLink>
+<BadgeLink badgeText='Read' href='https://www.digitalocean.com/community/tutorials/an-introduction-to-graphql'>Digital Ocean: An Introduction to GraphQL</BadgeLink>
+<BadgeLink badgeText='Read' href='https://www.howtographql.com/'>How to GraphQL: The Fullstack Tutorial for GraphQL</BadgeLink>
+<BadgeLink badgeText='Watch' colorScheme="red" href='https://www.youtube.com/watch?v=ed8SzALpx1Q'>GraphQL Full Course - Novice to Expert (by freeCodeCamp.org on YouTube)</BadgeLink>
+<BadgeLink badgeText='Watch' colorScheme="red" href='https://www.youtube.com/playlist?list=PLN3n1USn4xln0j_NN9k4j5hS1thsGibKi'>Beginner GraphQL Series (by Ben Awad on YouTube)</BadgeLink>