Querystring in url is ignored

[tommybo-entur]

Describe the bug
I'm trying to connect to a GraphQL service that require us to pass an identifier through the querystring in the url. The url looks something like this: https://app.myservice.com/api/graphql?myIdentifier=SomeString. When I save and test the datasource an error is shown stating that we receive a http-response with status code 400. I have to inspect the network traffic to find the error returned from the service, which in turn states something in the lines of "myIdentifier can not be empty"

Expected behavior
I expect the service to accept the request according to the query parameters set in the url

Screenshots