support/testing: test_python_rsa: increase timeout

On some developers machines, the default timeout (5 seconds) is not
enough for the test to succeed.

Increase it to 20 seconds, to let more time for the rsa keys to be
generated.

Signed-off-by: Raphaël Mélotte <raphael.melotte@mind.be>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

support/testing/tests/package/test_python_rsa.py

@@ -9,3 +9,4 @@ class TestPythonPy3RSA(TestPythonPackageBase):
         BR2_PACKAGE_PYTHON_RSA=y
         """
     sample_scripts = ["tests/package/sample_python_rsa.py"]
+    timeout = 20