Tests: remove fedoratest and replace it with test_distro

fedoratest was yet another dummy distribution used by unit tests. After
the rework of test_distro, there is no reason to not use it as the only
distro implementation for testing purposes.

Remove fedoratest distro and replace it with test_distro in all affected
tests.

Signed-off-by: Tomas Hozza <thozza@redhat.com>

internal/client/integration_test.go

@@ -20,7 +20,8 @@ var testState *TestState
 // Also makes sure there is a running server to test against
 func executeTests(m *testing.M) int {
 	var err error
-	testState, err = setUpTestState("/run/weldr/api.socket", false)
+
+	testState, err = setUpTestState("/run/weldr/api.socket", "qcow2", false)
 	if err != nil {
 		fmt.Printf("ERROR: Test setup failed: %s\n", err)
 		panic(err)