chore(deps): bump spring-boot-starter-parent in /mvc-thymeleaf

Bumps [spring-boot-starter-parent](https://github.com/spring-projects/spring-boot) from 2.5.6 to 2.5.7.
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](spring-projects/spring-boot@v2.5.6...v2.5.7)

---
updated-dependencies:
- dependency-name: org.springframework.boot:spring-boot-starter-parent
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

mvc-thymeleaf/pom.xml

@@ -14,7 +14,7 @@
     <parent>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-parent</artifactId>
-        <version>2.5.6</version>
+        <version>2.5.7</version>
         <relativePath/> <!-- lookup parent from repository -->
     </parent>