build(deps): bump spring-boot-starter-log4j2 from 2.6.3 to 2.6.4

Bumps [spring-boot-starter-log4j2](https://github.com/spring-projects/spring-boot) from 2.6.3 to 2.6.4.
- [Release notes](https://github.com/spring-projects/spring-boot/releases)
- [Commits](https://github.com/spring-projects/spring-boot/compare/v2.6.3...v2.6.4

)

---
updated-dependencies:
- dependency-name: org.springframework.boot:spring-boot-starter-log4j2
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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