[BUG] Empty IOC indices created even when source config index creation fails

[jowg-amazon]

What is the bug?
When creating a threat intel source config, if downloading ioc indices is not successful, the ioc index still gets created as an empty index even though the source config is deleted.

How can one reproduce the bug?
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4. See error

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: 2.15
• Plugins

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