Update dependency io.undertow:undertow-core to v2.3.18.Final

Author: renovate[bot]

pom.xml

@@ -18,7 +18,7 @@
         <dependency>
             <groupId>io.undertow</groupId>
             <artifactId>undertow-core</artifactId>
-            <version>2.3.1.Final</version>
+            <version>2.3.18.Final</version>
         </dependency>
     </dependencies>