Fix dependency error with org.eclipse.jetty.jetty

This is only used by reflection, and should be provided by the servlet
container (Tomcat or Jetty).

airsonic-main/pom.xml

@@ -492,6 +492,13 @@
             <scope>provided</scope>
         </dependency>
 
+        <!-- Provided by the servlet container, but found by dependency:analyze even if used via reflection -->
+        <dependency>
+          <groupId>org.eclipse.jetty</groupId>
+          <artifactId>jetty-io</artifactId>
+          <scope>provided</scope>
+        </dependency>
+
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>
             <artifactId>jackson-core</artifactId>