Bump spring-security-bom from 5.4.5 to 5.4.6

Bumps [spring-security-bom](https://github.com/spring-projects/spring-security) from 5.4.5 to 5.4.6.
- [Release notes](https://github.com/spring-projects/spring-security/releases)
- [Changelog](https://github.com/spring-projects/spring-security/blob/master/RELEASE.adoc)
- [Commits](https://github.com/spring-projects/spring-security/compare/5.4.5...5.4.6

)

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