added the spring boot Application class

src/main/java/eu/dnetlib/repo/manager/Application.java

@@ -0,0 +1,12 @@
+package eu.dnetlib.repo.manager;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class Application {
+
+    public static void main(String[] args) {
+        SpringApplication.run(Application.class, args);
+    }
+}