fix(deps): update dependency org.htmlunit:neko-htmlunit to v4.21.0

Author: renovate[bot]

pom.xml

@@ -77,7 +77,7 @@
             <dependency>
                 <groupId>org.htmlunit</groupId>
                 <artifactId>neko-htmlunit</artifactId>
-                <version>4.20.1</version>
+                <version>4.21.0</version>
             </dependency>
             <dependency>
                 <groupId>junit</groupId>