tests: unit-tests-{core,tools} no longer require a global io_service

BaseFixture is moved to tests/daemon and renamed to GlobalIoFixture

Refs: #4528
Change-Id: If9184e9f7f1d6072b0103d3ea3ca6c31a9e505c8
diff --git a/tests/daemon/face/channel-fixture.hpp b/tests/daemon/face/channel-fixture.hpp
index 8f94a09..3e13095 100644
--- a/tests/daemon/face/channel-fixture.hpp
+++ b/tests/daemon/face/channel-fixture.hpp
@@ -28,6 +28,7 @@
 
 #include "face/channel.hpp"
 
+#include "tests/test-common.hpp"
 #include "tests/daemon/limited-io.hpp"
 
 #include <type_traits>
@@ -39,7 +40,7 @@
 using namespace nfd::tests;
 
 template<class ChannelT, class EndpointT>
-class ChannelFixture : public BaseFixture
+class ChannelFixture : public GlobalIoFixture
 {
   static_assert(std::is_base_of<Channel, ChannelT>::value,
                 "ChannelFixture must be instantiated with a type derived from Channel");