title: Kotlin multiplatform test error ("Error_0: Fail to fetch")
body: <p>I have a kotlin-multiplatform project that has a kotlinJS client and a JVM backend. I'm creating some integration tests that are supposed to test the API calls from the client. The function is a suspend function with an HttpClient call with a POST method. I'm using kotlinx-coroutines-test, the test looks like this:</p>
  <pre class="lang-kotlin prettyprint-override"><code>@OptIn(ExperimentalCoroutinesApi::class)
  @Test
  fun testGetSingleResult() = runTest {
     val result = getSingleResult(TESTED_ID)
     assertThat(result.ID).isEqualTo(TESTED_ID)
  }
  </code></pre>
  <p>It should call the server in localhost:8080 and receive the result with the given ID. Instead of that, it gives the following error:</p>
  <pre><code>Error_0: Fail to fetch
  Error_0: Fail to fetch
      at &lt;global&gt;.&lt;unknown&gt;(/tmp/_karma_webpack_59097/commons.js:148488)
  ...
  FAILURE: Build failed with an exception.
  * What went wrong:
  Execution failed for task ':jsBrowserTest'.
  </code></pre>
  <p>I don't know what's happening, I thought that maybe the test is not launching the backend, so it won't find it when doing the request but I tried running the app at the same time that I launched the test and nothing changed.</p>
  <p>EDIT:
  <a href="https://github.com/IAAA-Lab/space-ql/blob/main/build.gradle.kts" rel="nofollow noreferrer">Here</a> is my build.gradle file and the link to the project.</p>