fix(useAxios): assign AxiosError to error.value when no url provided (close #2478)

[yysuen]

Description

Fixes #2478 .

Test case missing url for useAxios expects error.value to be defined when url is missing. However, currently it is undefined.

I assigned an AxioxError to error.value when url is missing at calling useAxios.

const execute: OverallUseAxiosReturn<T, R, D>['execute'] = (executeUrl: string | AxiosRequestConfig<D> | undefined = url, config: AxiosRequestConfig<D> = {}) => {
    error.value = undefined
-    const _url = typeof executeUrl === 'string'
+    let _url = typeof executeUrl === 'string'
      ? executeUrl
-      : url ?? ''
+      : url ?? config.url

+    if (_url === undefined) {
+     error.value = new AxiosError(AxiosError.ERR_INVALID_URL)
+      _url = ''
+   }

    loading(true)
    instance(_url, { ...defaultConfig, ...typeof executeUrl === 'object' ? executeUrl : config, cancelToken: cancelToken.token })
      .then((r: any) => {
        response.value = r
        data.value = r.data
      })
      .catch((e: any) => {
        error.value = e
      })
      .finally(() => loading(false))
    return { then }
  }

Test case missing url is now passing with this PR.

Additional context

Null.

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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