docs: remove stray ; (#102)

Author: jackdclark

README.md

@@ -151,7 +151,7 @@ const client = new GraphQLClient(config)
 
 ```js
 import { ClientContext } from 'graphql-hooks'
-;<ClientContext.Provider value={client}>
+<ClientContext.Provider value={client}>
   {/* children can now consume the client context */}
 </ClientContext.Provider>
 ```