Upgrade to Spring 6 and Spring Boot 3.

See #654

couchbase/example/pom.xml

@@ -22,6 +22,11 @@
 			<scope>test</scope>
 		</dependency>
 
+		<dependency>
+			<groupId>jakarta.annotation</groupId>
+			<artifactId>jakarta.annotation-api</artifactId>
+		</dependency>
+
 	</dependencies>
 
 </project>

couchbase/example/src/main/java/example/springdata/couchbase/repository/CouchbaseMain.java

@@ -18,7 +18,7 @@ package example.springdata.couchbase.repository;
 import example.springdata.couchbase.model.Airline;
 import lombok.RequiredArgsConstructor;
 
-import javax.annotation.PostConstruct;
+import jakarta.annotation.PostConstruct;
 
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.autoconfigure.SpringBootApplication;