QA: Use own unit test headers for eagle test

These include the appropriate "polyfills" for things like
Boost versions.

qa/eeschema/test_eagle_plugin.cpp

@@ -22,8 +22,8 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
  */
 
-#include <boost/test/test_case_template.hpp>
-#include <boost/test/unit_test.hpp>
+#include <unit_test_utils/unit_test_utils.h>
+
 #include <kiway.h>
 #include <sch_io_mgr.h>