调整 spring-boot-starter 依赖为可选

[mercyblitz]

将

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>

修改成

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
            <optional>true</optional>
        </dependency>

减少 spring-boot-starter 依赖侵入