Update jackson-bom to 2.12.3

Closes spring-projectsgh-9616

Author: rwinch

dependencies/spring-security-dependencies.gradle

@@ -13,7 +13,7 @@ dependencies {
 	api platform("org.springframework.data:spring-data-bom:2020.0.7")
 	api platform("org.jetbrains.kotlin:kotlin-bom:$kotlinVersion")
 	api platform("org.jetbrains.kotlinx:kotlinx-coroutines-bom:1.4.3")
-	api platform("com.fasterxml.jackson:jackson-bom:2.12.2")
+	api platform("com.fasterxml.jackson:jackson-bom:2.12.3")
 	constraints {
 		api "ch.qos.logback:logback-classic:1.2.3"
 		api "com.google.inject:guice:3.0"