Bump spring-core from 4.3.16.RELEASE to 5.2.24.RELEASE

Bumps [spring-core](https://github.com/spring-projects/spring-framework) from 4.3.16.RELEASE to 5.2.24.RELEASE.
- [Release notes](https://github.com/spring-projects/spring-framework/releases)
- [Commits](https://github.com/spring-projects/spring-framework/compare/v4.3.16.RELEASE...v5.2.24.RELEASE)

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

Signed-off-by: dependabot[bot] <support@github.com>
diff --git a/pom.xml b/pom.xml
index 15839cb..1cb4f2b 100644
--- a/pom.xml
+++ b/pom.xml
@@ -36,7 +36,7 @@
         <java.source.version>1.8</java.source.version>
         <java.target.version>1.8</java.target.version>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <spring.version>4.3.16.RELEASE</spring.version>
+        <spring.version>5.2.24.RELEASE</spring.version>
         <rocket.version>4.9.3</rocket.version>
         <prometheus.version>0.12.0</prometheus.version>
         <grpc-java.version>1.24.0</grpc-java.version>