develop: update serverless to starter

[lilin90]

What is changed, added or deleted? (Required)

Updates "Create Cluster 页面默认选择 Serverless" to "Create Cluster 页面默认选择 Starter" in develop/dev-guide-build-cluster-in-cloud.md

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[LGTM Timeline notifier]

Timeline:

• 2025-07-09 05:52:40.760027521 +0000 UTC m=+2065413.483206531: ☑️ agreed by qiancai.