Bump spring-boot-starter-web in /sample-maven-spring (#812)

Bumps [spring-boot-starter-web](https://github.com/spring-projects/spring-boot) from 2.5.6 to 2.5.12.
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](spring-projects/spring-boot@v2.5.6...v2.5.12)

---
updated-dependencies:
- dependency-name: org.springframework.boot:spring-boot-starter-web
  dependency-type: direct:production
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

sample-maven-spring/pom.xml

@@ -16,7 +16,7 @@
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-web</artifactId>
-            <version>2.5.6</version>
+            <version>2.5.12</version>
         </dependency>
     </dependencies>