--dgraph_lambda_url flag missing on 21.03.0

When posting a schema that uses the @lambdaOnMutate directive, this error comes up:

{"errors":[{"message":"resolving updateGQLSchema failed because input:1: Type Author: has the @lambdaOnMutate directive, but the –graphql_lambda_url flag wasn't specified during alpha startup.\n (Locations: [{Line: 3, Column: 4}])","extensions":{"code":"Error"}}]}(base)

But when I add that flag to my alpha node, it complains that the flag is unknown:

./dgraph alpha --graphql_lambda_url
Error: unknown flag: --graphql_lambda_url

I’m using the latest 21.03.0 binary fetched via curl.

Dgraph version   : v21.03.0
Dgraph codename  : rocket
Dgraph SHA-256   : b4e4c77011e2938e9da197395dbce91d0c6ebb83d383b190f5b70201836a773f
Commit SHA-1     : a77bbe8ae
Commit timestamp : 2021-04-07 21:36:38 +0530
Branch           : HEAD

Please fix the error message.

I found the correct flag in the docs
dgraph alpha --graphql lambda-url=http://localhost:8686/graphql-worker

@hardik I accepted this issue - it’s a very small issue. Could you please assign a dev?