Create order-service walking skeleton

[heymaaz]

Create a new Spring Boot microservice with the name "order-service" and add the following features:

• Add dependencies Web, Validation, Spring Data JPA, Flyway, PostgreSQL, Spring for RabbitMQ, Resilience4J, Actuator, Prometheus, DevTools, Configuration Processor, Testcontainers
• Add springdoc-openapi dependency
• Add rest-assured dependency
• Add git-commit-id-maven-plugin
• Add spotless-maven-plugin
• Add PostgreSQL and RabbitMQ to deployment/docker-compose/infra.yml
• Add GitHub Action workflow for order-service
• Create Flyway Migration scripts for creating orders and order_items tables
• Configure spring-boot-maven-plugin to create a docker image with the name heymaaz/bookstore-order-service