fix: samples/client/echo_api/java/resttemplate/pom.xml to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JAVA-ORGSPRINGFRAMEWORK-15701755

Author: snyk-bot

samples/client/echo_api/java/resttemplate/pom.xml

@@ -277,7 +277,7 @@
         <jackson-version>2.19.2</jackson-version>
         <jackson-databind-version>2.19.2</jackson-databind-version>
         <jackson-databind-nullable-version>0.2.7</jackson-databind-nullable-version>
-        <spring-web-version>5.3.33</spring-web-version>
+        <spring-web-version>6.2.17</spring-web-version>
         <jakarta-annotation-version>1.3.5</jakarta-annotation-version>
         <beanvalidation-version>2.0.2</beanvalidation-version>
         <junit-version>5.10.2</junit-version>