Add Jsonb support

Spring Framework 5 will support Jsonb as a HttpMessageConverter, this
commit adds auto-configuration support. Also, support for Jsonb in the
@JsonTest has been added.

This implementation is running against Apache Johnzon

See gh-9648

spring-boot-test/pom.xml

@@ -45,6 +45,11 @@
 			<artifactId>reactor-netty</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>javax.json.bind</groupId>
+			<artifactId>javax.json.bind-api</artifactId>
+			<optional>true</optional>
+		</dependency>
 		<dependency>
 		<groupId>javax.servlet</groupId>
 			<artifactId>javax.servlet-api</artifactId>
@@ -116,6 +121,11 @@
 			<optional>true</optional>
 		</dependency>
 		<!-- Test -->
+		<dependency>
+			<groupId>javax.json</groupId>
+			<artifactId>javax.json-api</artifactId>
+			<scope>test</scope>
+		</dependency>
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-test-support</artifactId>
@@ -142,6 +152,11 @@
 			<optional>true</optional>
 			<scope>test</scope>
 		</dependency>
+		<dependency>
+			<groupId>org.apache.johnzon</groupId>
+			<artifactId>johnzon-jsonb</artifactId>
+			<scope>test</scope>
+		</dependency>
 		<dependency>
 			<groupId>org.jetbrains.kotlin</groupId>
 			<artifactId>kotlin-runtime</artifactId>