Move plugin specific tests into dedicated directory

This will prove beneficial when we also add tests for the policy engine
plugins. The increased locality is also nice to have.

plugins/provider/tests/setup-origin.h

@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2018 Purism SPC
+ *
+ * SPDX-License-Identifier: GPL-3.0+
+ */
+
+#include "setup-provider.h"
+#include "calls-dummy-origin.h"
+
+#define TEST_ORIGIN_NAME "Test Dummy origin"
+
+#define TEST_CALL_NUMBER "0123456789"
+
+typedef struct {
+  ProviderFixture   parent;
+  CallsDummyOrigin *dummy_origin;
+} OriginFixture;
+
+void test_dummy_origin_set_up (OriginFixture *fixture, gconstpointer user_data);
+void test_dummy_origin_tear_down (OriginFixture *fixture, gconstpointer user_data);