Add sample code to measure latency on TextEmbeddingModel

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**The issue you're having must be related to a file in this repository.** We are unable to provide assistance for issues unrelated to samples in this repository.

Please include as much information as possible:

## Is your feature request related to a problem? Please describe.
Customer is looking for an authoritative way to properly measure the latency on a given model of TextEmbeddingModel

## Describe the solution you'd like.
I would like to contribute by adding a new file with a code to send a given text N times, measure the time on each request and grouping them in percentiles 50, 95 and 99.

## Describe alternatives you've considered.
I have not thought on any other alternative.

## Additional context.
This is useful for those early adapters who want to make sure and confirm that this is indeed a reliable solution for the enterprise.

Making sure to follow these steps will guarantee the quickest resolution possible.

Thanks!