fix: such response type should just return themself not return a string

[lianghx-319]

Why

When my application load .wasm file from xhr, method getResonseByResponseType make respone become a string. I think just return the origin response is make sense.

[tencent-adm]

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[Maizify]

For a non-string response, it may not be displayed correctly on HTML, so I converted it to a string. If the original response is returned directly, how to ensure that it is displayed correctly in HTML?

[lianghx-319]

For a non-string response, it may not be displayed correctly on HTML, so I converted it to a string. If the original response is returned directly, how to ensure that it is displayed correctly in HTML?

But when I request a wasm file, this proxy will make wasm init fail, because the response changed.