support/testing: test_python_txaio: include twisted sample

Prior to b7d251293a20, txaio would test both asyncio and twisted.

Add back the twisted sample and include the twisted package in the
config so both modes of the package are tested.

Fixes: b7d251293a20 ("package/python-txaio: drop python 2 support")
Signed-off-by: Vincent Fazio <vfazio@xes-inc.com>
Signed-off-by: Julien Olivain <ju.o@free.fr>

support/testing/tests/package/test_python_txaio.py

@@ -7,5 +7,6 @@ class TestPythonPy3Txaio(TestPythonPackageBase):
         """
         BR2_PACKAGE_PYTHON3=y
         BR2_PACKAGE_PYTHON_TXAIO=y
+        BR2_PACKAGE_PYTHON_TWISTED=y
         """
-    sample_scripts = ["tests/package/sample_python_txaio_asyncio.py"]
+    sample_scripts = ["tests/package/sample_python_txaio_asyncio.py", "tests/package/sample_python_txaio_twisted.py"]