Problema com permissao de escrita nos testes

[ErickBrth]

══╡ EXCEPTION CAUGHT BY FLUTTER TEST FRAMEWORK ╞════════════════════════════════════════════════════
The following FileSystemException was thrown while running async test code:
Creation failed, path = '/C:' (OS Error: Read-only file system, errno = 30)

o que fiz:

adicionei as linhas no AndroidManifest.xml na pasta main:
android:icon="@mipmap/ic_launcher"
android:requestLegacyExternalStorage="true">

segue o arquivo AndroidManifest.xml completo:

    </activity>
    <!-- Don't delete the meta-data below.
         This is used by the Flutter tool to generate GeneratedPluginRegistrant.java -->
    <meta-data
        android:name="flutterEmbedding"
        android:value="2" />
</application>