fix typo Update hello_linera.md (#185)

src/developers/getting_started/hello_linera.md

@@ -127,7 +127,7 @@ linera service
 
 <!-- TODO: add graphiql image here -->
 
-Navigate to `http://localhost:8080` in your browser to access the GraphiQL, the
+Navigate to `http://localhost:8080` in your browser to access GraphiQL, the
 [GraphQL](https://graphql.org) IDE. We'll look at this in more detail in a
 [later section](../core_concepts/node_service.md#graphiql-ide); for now, list
 the applications deployed on your default chain e476… by running: