ti_util: include package in threat_intel category

[efd6]

What does this PR do?

This adds the ti_util package to the threat_intel category.

Checklist

• I have reviewed tips for building integrations and this pull request is aligned with them.
• I have verified that all data streams collect metrics or logs.
• I have added an entry to my package's changelog.yml file.
• I have verified that Kibana version constraints are current according to guidelines.

Author's Checklist

• [ ]

How to test this PR locally

Related issues

• Closes [ti_util] Add 'threat_intel' category #4176

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• Start Time: 2022-09-12T08:49:47.159+0000

• Duration: 20 min 50 sec

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