misc: update documentation

Author: Miaxos

Cargo.toml

@@ -5,7 +5,7 @@ authors = ["Anthony Griffon <[email protected]>"]
 description = "An async_graphql extension to send traces & metrics to Apollo Studio"
 readme = "README.md"
 repository = "https://github.com/async-graphql/async_graphql_apollo_studio_extension"
-documentation = "https://github.com/async-graphql/async_graphql_apollo_studio_extension"
+documentation = "https://docs.rs/async-graphql-extension-apollo-tracing"
 license = "MIT"
 keywords = ["async_graphql", "async", "graphql", "apollo", "studio"]
 categories = ["network-programming", "asynchronous"]