fix: webmagic-samples/pom.xml to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JAVA-COMFASTERXMLJACKSONCORE-3038424

Author: snyk-bot

webmagic-samples/pom.xml

@@ -42,7 +42,7 @@
         <dependency>
             <groupId>com.fasterxml.jackson.core</groupId>
             <artifactId>jackson-databind</artifactId>
-            <version>2.13.2.1</version>
+            <version>2.13.4</version>
         </dependency>
     </dependencies>