[BUG] invalid data source id should throw 4xx error

[BionIT]

Describe the bug

Similar to how decide client works, if data source id is not empty and has data source enabled then use data source client, otherwise we should use the opensearch or legacy client.

OpenSearch-Dashboards/src/plugins/data_source/common/util/decide_client.ts

Line 16 in a0365d8

export const decideClient = async (

To Reproduce
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Expected behavior
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OpenSearch Version
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Dashboards Version
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Plugins

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Host/Environment (please complete the following information):

• OS: [e.g. iOS]
• Browser and version [e.g. 22]

Additional context

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