Use GraphQL Logo in README.md that looks nicer (#759)

Co-authored-by: Benjie Gillam <[email protected]>

Author: raihan71

README.md

@@ -1,5 +1,7 @@
 # GraphQL
 
+<img alt="GraphQL Logo" align="right" src="resources/GraphQL%20Logo.svg" width="15%" />
+
 The GraphQL specification is edited in the markdown files found in [`/spec`](./spec)
 the latest release of which is published at https://graphql.github.io/graphql-spec/.