[Improvement][HTTP] support customization of the JSON format in http body

[Gallardot]

Search before asking

• I had searched in the issues and found no similar feature requirement.

Description

The current HTTP task only supports setting the HTTP body through http_parameters, and the body only supports JSON format where the value of the JSON is limited to strings. For example:

{
    "key1": "value1",
    "key2": "value2"
}

Allowing customization of the JSON format would further enhance the flexibility of HTTP tasks. For instance, supporting the following format:

{
    "key1": "value1",
    "key2": {
        "int": 123,
        "boolean": true,
        "array": [1, 2, 3]
    }
}

Are you willing to submit a PR?

• Yes I am willing to submit a PR!

Code of Conduct

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