Feature/crows pairs

[alytarik]

Description

This PR aims to include Crows-Pairs dataset in langtest. This test uses a masked sentence and two tokens to decide whether the model has bias for/against one choice.

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➤ Fixes #728

Type of change

• New feature (non-breaking change which adds functionality)

Usage

Tutorial Notebook

harness = Harness(
    data={"data_source":"Crows-Pairs"},
    model={"model":"bert-base-uncased", "hub":"huggingface"},
    task="crows-pairs",
    config={
    "tests": {
        "defaults": {
            "min_pass_rate": 1.0
        },
        "crows-pairs": {
            "common-stereotypes": {
                "min_pass_rate": 0.70
            }
        }
    }
})

Checklist:

• I've added Google style docstrings to my code.
• I've used pydantic for typing when/where necessary.
• I have linted my code
• I have added tests to cover my changes.

Screenshots (if appropriate):