Remove jackson-datatype-jdk8 dependency for now

This dependency breaks Glassfish integration tests and was not strictly
required by #9297.

Author: snicoll

spring-boot-starters/spring-boot-starter-json/pom.xml

@@ -22,10 +22,6 @@
 			<groupId>com.fasterxml.jackson.core</groupId>
 			<artifactId>jackson-databind</artifactId>
 		</dependency>
-		<dependency>
-			<groupId>com.fasterxml.jackson.datatype</groupId>
-			<artifactId>jackson-datatype-jdk8</artifactId>
-		</dependency>
 		<dependency>
 			<groupId>com.fasterxml.jackson.datatype</groupId>
 			<artifactId>jackson-datatype-jsr310</artifactId>