Bump spring-security-version in /simple-users

Bumps `spring-security-version` from 5.2.2.RELEASE to 5.3.4.RELEASE.

Updates `spring-security-core` from 5.2.2.RELEASE to 5.3.4.RELEASE
- [Release notes](https://github.com/spring-projects/spring-security/releases)
- [Commits](spring-projects/spring-security@5.2.2.RELEASE...5.3.4.RELEASE)

Updates `spring-security-config` from 5.2.2.RELEASE to 5.3.4.RELEASE
- [Release notes](https://github.com/spring-projects/spring-security/releases)
- [Commits](spring-projects/spring-security@5.2.2.RELEASE...5.3.4.RELEASE)

Updates `spring-security-taglibs` from 5.2.2.RELEASE to 5.3.4.RELEASE
- [Release notes](https://github.com/spring-projects/spring-security/releases)
- [Commits](spring-projects/spring-security@5.2.2.RELEASE...5.3.4.RELEASE)

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

simple-users/pom.xml

@@ -38,7 +38,7 @@
 	<properties>
 		<org.slf4j-version>1.7.5</org.slf4j-version>
 		<org.springframework-version>5.1.5.RELEASE</org.springframework-version>
-		<spring-security-version>5.2.4.RELEASE</spring-security-version>
+		<spring-security-version>5.3.4.RELEASE</spring-security-version>
 		<spring-data.version>Lovelace-RELEASE</spring-data.version>
 		<thymeleaf.version>3.0.11.RELEASE</thymeleaf.version>