GH-1192 - Migrate code base to jSpecify for nullness verification.

spring-modulith-examples/pom.xml

@@ -118,6 +118,11 @@
 
 	<dependencies>
 
+		<dependency>
+			<groupId>org.jspecify</groupId>
+			<artifactId>jspecify</artifactId>
+		</dependency>
+
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter</artifactId>