Update timed_out to timeouts and replace value with a count value

[jcstorms1]

What does this PR do?

Updates the name of aws.enhanced.lambda.timed_out to aws.enhanced.lambda.timeouts
Changes the value of the metric to count time out function occurrences.

Motivation

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
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