Añadidas las interfaces para los test

src/test/java/inf/uva/es/ivagonz/practica4/Integration.java

+package inf.uva.es.ivagonz.practica4;
+
+public interface Integration {
+
+}

src/test/java/inf/uva/es/ivagonz/practica4/Isolation.java

+package inf.uva.es.ivagonz.practica4;
+
+public interface Isolation {
+
+}

src/test/java/inf/uva/es/ivagonz/practica4/Unit.java

+package inf.uva.es.ivagonz.practica4;
+
+public interface Unit {
+
+}