chore(deps): bump org.springframework.boot:spring-boot-starter-mail

Bumps [org.springframework.boot:spring-boot-starter-mail](https:/spring-projects/spring-boot) from 3.2.2 to 3.3.4.
- [Release notes](https:/spring-projects/spring-boot/releases)
- [Commits](spring-projects/spring-boot@v3.2.2...v3.3.4)

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

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

backend/pom.xml

@@ -84,7 +84,7 @@
  <dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-mail</artifactId>
- <version>3.2.2</version>
+ <version>3.3.4</version>
  </dependency>
  <dependency>
  <groupId>org.springframework.boot</groupId>