vici: Move Python test dir and include it in sdist

This is the recommended location and import config as it allows running the
tests against installed versions of the package.  And while the test file
itself is automatically included in the source distribution this way, the
__init__.py file is not, so we still have to update MANIFEST.in.

src/libcharon/plugins/vici/python/Makefile.am

@@ -2,8 +2,8 @@ EXTRA_DIST = LICENSE README.rst MANIFEST.in \
 	setup.py.in \
 	tox.ini \
 	tox.sh \
-	vici/test/__init__.py \
-	vici/test/test_protocol.py \
+	test/__init__.py \
+	test/test_protocol.py \
 	vici/__init__.py \
 	vici/command_wrappers.py \
 	vici/compat.py \