Upgrade sparkjava

Author: adhesivee

oauth2-server-sparkjava/pom.xml

@@ -15,7 +15,7 @@
         <dependency>
             <groupId>com.sparkjava</groupId>
             <artifactId>spark-core</artifactId>
-            <version>2.5.4</version>
+            <version>2.8.0</version>
             <scope>provided</scope>
         </dependency>
         <dependency>