fix: samples/server/petstore/springboot-reactive/pom.xml to reduce vu…

…lnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARS-6056394
- https://snyk.io/vuln/SNYK-JAVA-ORGYAML-6056527

samples/server/petstore/springboot-reactive/pom.xml

@@ -48,7 +48,7 @@
         <dependency>
             <groupId>org.webjars</groupId>
             <artifactId>swagger-ui</artifactId>
-            <version>3.14.2</version>
+            <version>4.1.3</version>
         </dependency>
         <dependency>
             <groupId>io.swagger</groupId>