Mturk create-qualification-type [--test <value>] format

Confirm by changing [ ] to [x] below:
- [x] I've gone though the [User Guide](https://docs.aws.amazon.com/cli/latest/userguide/cli-chap-welcome.html) and the [API reference](https://docs.aws.amazon.com/cli/latest/reference/)
- [x] I've searched for [previous similar issues](https://github.com/aws/aws-cli/issues) and didn't find any solution

Issue is about usage on:
- [ ] Service API : I want to do X using Y service, what should I do?
- [x] CLI : passing arguments or cli configurations.
- [ ] Other/Not sure.

**Platform/OS/Hardware/Device**
What are you running the cli on?
- macOS Catalina 10.15.5
- aws-cli/2.0.16 Python/3.7.3 Linux/4.19.76-linuxkit botocore/2.0.0dev20

**Describe the question**

Using the requester sandbox `--endpoint-url https://mturk-requester-sandbox.us-east-1.amazonaws.com` I would like to create a qualification type with a test and answer key.

According to the documentation I can use 2 optional options `[--test ] and [--answer-key ]` (while not forgetting `--test-duration-in-seconds `).

https://awscli.amazonaws.com/v2/documentation/api/latest/reference/mturk/create-qualification-type.html

Using Qualification test and answer key require particular structures defined here:

https://docs.aws.amazon.com/AWSMechTurk/latest/AWSMturkAPI/ApiReference_QuestionFormDataStructureArticle.html

https://docs.aws.amazon.com/AWSMechTurk/latest/AWSMturkAPI/ApiReference_AnswerKeyDataStructureArticle.html

Is it possible to have an example how do you pass the content to the `aws mturk create-qualification-type ...` options:
- `--test `
- `--answer-key `

Thxs

Start with the AWS CLI create-qualification-type reference and the linked QuestionFormData and AnswerKeyData structure documentation. Verify how the --test and --answer-key values are passed, then document complete command examples that work with the requester sandbox endpoint and include the required test duration.

Written by the indexing model from the issue text.