Use unknown type instead of any for Typescript definitions of response types

[AsazuTaiga]

Is your feature request related to a problem? Please describe.

I strongly sympathize with issue #3313, which was closed by BOT, and feel that it is an issue worth considering, so I will raise another issue with the same content.

Describe the solution you'd like

I think that the type argument of the response should be changed from <T = any> to <T = unknown>.

// <T = any>
const asyncFunction = async () => {
  const response = await axios.get('/path/to/endpoint')
  const data = response.data // any 😢
  const foo = data.foo // not type error, but foo may be undefined
  // ...
}

// if <T = unknown>
const asyncFunction = async () => {
  const response = await axios.get('/path/to/endpoint')
  const data = response.data // unknown
  // const foo= data.foo // type error
  if (hasFoo(data)) { // type testing is compulsory 😄 
    const foo = data.foo
    // ...
  }
}

Describe alternatives you've considered

This may be breaking changes, so it might be a good idea to just document the following wrappers.

async function typeSafeGet<T = unknown>(
  url: string,
  config?: AxiosRequestConfig,
) {
  return axios.get<T>(url, config)
}

Additional context

In #3002, @carloschida agrees that unknown is optimal choice.

[carloschida]

I also proposed a change in #2995.

[AsazuTaiga]

Thank you very much.
I wasn't aware of the PR on your side, sorry about that.
I think this issue is no longer needed, so I'll close it!