specify service annotation protocol

[haiyang1985]

What is the purpose of the change

For Issue #5049

Brief changelog

XXXXX

Verifying this change

XXXXX

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[mercyblitz]

You could create a bean of DubboConfigBeanCustomizer to add the alias that you want

[mercyblitz]

getBean method will cause the initialization of ProtocolConfig's bean too early

[sonymoon]

getBean method will cause the initialization of ProtocolConfig's bean too early

I have created a PR #5063.. to avoid the eager initialization of ProtocolConfig's bean

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