Update spring core to v5.3.21

Author: renovate[bot]

pom.xml

@@ -16,7 +16,7 @@
 		<dependency>
 			<groupId>org.springframework</groupId>
 			<artifactId>spring-core</artifactId>
-			<version>5.2.4.RELEASE</version>
+			<version>5.3.21</version>
 		</dependency>
 		<dependency>
 			<groupId>org.springframework</groupId>
@@ -31,7 +31,7 @@
 		<dependency>
 			<groupId>org.springframework</groupId>
 			<artifactId>spring-beans</artifactId>
-			<version>5.2.4.RELEASE</version>
+			<version>5.3.21</version>
 		</dependency>
 		<!-- Apache CXF Dependencies -->
 		<dependency>