optimize the rocketmq-example and update rocketmq-a2a version

[zk-drizzle]

optimize the rocketmq-example and update rocketmq-a2a version

[cla-assistant]

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1 out of 2 committers have signed the CLA.

✅ chickenlj
❌ drizzle.zk

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[cla-assistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.

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drizzle.zk seems not to be a GitHub user. You need a GitHub account to be able to sign the CLA. If you have already a GitHub account, please add the email address used for this commit to your account.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}