Add product classes into domain.

build.gradle.kts

@@ -18,6 +18,12 @@ repositories {
 	mavenCentral()
 }
 
+subprojects {
+	repositories {
+		mavenCentral()
+	}
+}
+
 dependencies {
 	implementation("org.springframework.boot:spring-boot-starter-web")
 	implementation("com.fasterxml.jackson.module:jackson-module-kotlin")