Adding cloudtrail insight to the cloudtrail regex pattern

[thekevinhuang]

Adding Cloudtrail-Insight to the regex pattern so that Cloudtrail-Insight logs are marked with source of cloudtrail instead of default s3.

What does this PR do?

Adds Insight to the cloudtrail regex.

Motivation

Customer issue

Testing Guidelines

Additional Notes

Types of changes

• Bug fix
• New feature
• Breaking change
• Misc (docs, refactoring, dependency upgrade, etc.)

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• This PR's description is comprehensive
• This PR contains breaking changes that are documented in the description
• This PR introduces new APIs or parameters that are documented and unlikely to change in the foreseeable future
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