[BUG] MDS disabled API calls don't work

[derek-ho]

What is the bug?
When MDS is disabled, API calls are failing with "dataSourceId does not exist" errors - this is because after the introduction of MDS feature in #1888, the dataSourceId became a required field for API calls.

How can one reproduce the bug?
Check out main and try to navigate any tab in the security dashboards plugin, API calls fail and no data loads.

What is the expected behavior?
A clear and concise description of what you expected to happen.

What is your host/environment?

• OS: [e.g. iOS]
• Version [e.g. 22]
• Plugins

Do you have any screenshots?
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Do you have any additional context?
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