fix(XPack): 恢复被误删的类

backend/src/main/java/io/metersphere/service/LicenseService.java

@@ -0,0 +1,10 @@
+package io.metersphere.service;
+
+import io.metersphere.dto.LicenseDTO;
+
+public interface LicenseService {
+
+    public LicenseDTO valid();
+
+    public LicenseDTO addValidLicense(String reqLicenseCode);
+}