Typo in bpp-client.yaml-sample ("ttelemetry" should be "telemetry")

## Description

There's a small typo in the bpp-client.yaml-sample file. The key "ttelemetry" should be "telemetry". This leads to the config being invalidated due to which bpp-client does not start successfully.

## File
- bpp-client.yaml-sample

## Suggested Fix
Replace "ttelemetry" with "telemetry" to correct the typo.

## Environment
N/A

## Additional Context
N/A
