Update org.springframework.security to 5.6.3

Closes gh-651

Author: jzheaux

dependencies/build.gradle

@@ -59,9 +59,9 @@ dependencies {
 		api "org.slf4j:jcl-over-slf4j:1.7.32"
 		api "org.slf4j:log4j-over-slf4j:1.7.32"
 		api "org.slf4j:slf4j-api:1.7.32"
-		api "org.springframework.security:spring-security-config:5.6.1"
-		api "org.springframework.security:spring-security-core:5.6.1"
-		api "org.springframework.security:spring-security-ldap:5.6.1"
+		api "org.springframework.security:spring-security-config:5.6.3"
+		api "org.springframework.security:spring-security-core:5.6.3"
+		api "org.springframework.security:spring-security-ldap:5.6.3"
 		api "org.slf4j:slf4j-log4j12:1.7.32"
 		api "org.springframework.ldap:spring-ldap-core:2.3.4.RELEASE"
 	}