docstr: Test that the component handles files with unknown mime types.
code: def test_unknown_mime_type(self):
      """
      Test that the component handles files with unknown mime types.
      """
      with pytest.raises(ValueError, match="Unknown mime type:"):
          FileTypeRouter(mime_types=["type_invalid"])
  
file_path: haystack/test/components/routers/test_file_router.py
imports: import sys
  import pytest
  from haystack.components.routers.file_type_router import FileTypeRouter
  from haystack.dataclasses import ByteStream
label_desc: Use image node_id 7 for calling the TestFileTypeRouter obj's underlying member method code with example usage: obj.test_unknown_mime_type() without return types