Support --queryStringParameters parameter when generating api gateway aws-proxy event

### Describe your idea/feature/enhancement

I want to generate an API GW event to test my lambda locally. My lambda expects queryStringParameters.

I tried:
`sam local generate-event apigateway aws-proxy --method GET --path document --body "" --queryStringParameters "{"documentId": "1044", "versionId": "v_1"}"`

`Error: no such option: --queryStringParameters`

### Proposal

It's not clear how I can generate an event with custom queryStringParameters. I don't want to edit the json manually if possible.

It would be nice to have some thing like the parameter `--queryStringParameters` to make it easy to generate queryStringParameters inside the event.json