[R-293] Noise sensitivity metrics from RAGChecker

[shahules786]

RAGChecker from AWS has noise sensitivity metrics that could be useful to Ragas users

TBD

1. Implement metrics
2. Prepare docs to intuitively explain how it's calculated and how can it be used.

_R-293

[sky-2002]

Hey @shahules786 I will take up

[shahules786]

@sky-2002 Great, assigned to you.