Upgrade test source compile level to Java 17.

Also, remove custom Jackson library version for Hibernate integration.

Author: odrotbohm

spring-data-rest-tests/pom.xml

@@ -23,7 +23,6 @@
 
 	<properties>
 		<groovy.version>2.4.4</groovy.version>
-		<source.level>1.8</source.level>
 	</properties>
 
 	<dependencies>

spring-data-rest-tests/spring-data-rest-tests-jpa/pom.xml

@@ -59,7 +59,6 @@
 		<dependency>
 			<groupId>com.fasterxml.jackson.datatype</groupId>
 			<artifactId>jackson-datatype-hibernate5-jakarta</artifactId>
-			<version>2.13.4</version>
 		</dependency>
 
 	</dependencies>