Bump spring-security-core in /modules/spring-session-ext

Bumps [spring-security-core](https://github.com/spring-projects/spring-security) from 5.5.0 to 5.5.7.
- [Release notes](https://github.com/spring-projects/spring-security/releases)
- [Changelog](https://github.com/spring-projects/spring-security/blob/main/RELEASE.adoc)
- [Commits](https://github.com/spring-projects/spring-security/compare/5.5.0...5.5.7)

---
updated-dependencies:
- dependency-name: org.springframework.security:spring-security-core
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>
diff --git a/modules/spring-session-ext/pom.xml b/modules/spring-session-ext/pom.xml
index 72f725c..5c90065 100644
--- a/modules/spring-session-ext/pom.xml
+++ b/modules/spring-session-ext/pom.xml
@@ -35,7 +35,7 @@
 
     <properties>
         <spring.session.version>2.5.0</spring.session.version>
-        <spring.security.version>5.5.0</spring.security.version>
+        <spring.security.version>5.5.7</spring.security.version>
         <javax.annotation.version>1.3.2</javax.annotation.version>
         <assertj.version>3.20.0</assertj.version>
         <junit.jupiter.version>5.7.2</junit.jupiter.version>