feat(aws-cloudwatch): add missing cloudwatch statistics in exported e…

…num (`p`, `tm`, `iqm`, `wm`, `tc`, `ts`) (#23074)

Some statistics were missing from the lib `p`, `tm`, `iqm`, `wm`, `tc`, `ts`.

I added the most common ones in the exported enum, with a good documentation pulled from [AWS CloudWatch documentation - Statistics definitions](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/Statistics-definitions.html)

Fixes #21666 #14688

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