Bump spring-core from 5.3.19 to 5.3.20

Bumps [spring-core](https://github.com/spring-projects/spring-framework) from 5.3.19 to 5.3.20.
- [Release notes](https://github.com/spring-projects/spring-framework/releases)
- [Commits](https://github.com/spring-projects/spring-framework/compare/v5.3.19...v5.3.20)

---
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 c3334f3..73c4565 100644
--- a/pom.xml
+++ b/pom.xml
@@ -96,7 +96,7 @@
     <slf4j.version>1.7.32</slf4j.version>
     <log4j.version>2.17.1</log4j.version>
     <ehcache.version>3.9.9</ehcache.version>
-    <spring.version>5.3.19</spring.version>
+    <spring.version>5.3.20</spring.version>
     <cxf.version>3.3.11</cxf.version>
     <jackson.version>2.12.1</jackson.version>
     <hsqldb.version>2.5.0</hsqldb.version>