Fix luke docstring

[qqaatw]

What does this PR do?

The output logits of LukeForEntitySpanClassification is in (batch_size, entity_length, config.num_labels) shape instead of (batch_size, config.num_labels), which is that of LukeForEntityClassification.

transformers/tests/models/luke/test_modeling_luke.py

Lines 402 to 404 in 8b67f20

	self.parent.assertEqual(
	result.logits.shape, (self.batch_size, self.entity_length, self.num_entity_span_classification_labels)
	)

Fixes # (issue)

Before submitting

• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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• Did you write any new necessary tests?

Who can review?

@sgugger

Anyone in the community is free to review the PR once the tests have passed. Feel free to tag
members/contributors who may be interested in your PR.

[HuggingFaceDocBuilderDev]

The documentation is not available anymore as the PR was closed or merged.

[LysandreJik]

Indeed! Sounds good to me, @qqaatw, thank you for your contribution!