Update forced_align method to only support batch Tensors

[nateanl]

Summary: Current design of forced_align accept 2D Tensor for log_probs and 1D Tensor for targets. To make the API simple, the PR make changes to only support batch Tensors (3D Tensor for log_probs and 2D Tensor for targets).

Differential Revision: D46657526

[pytorch-bot]

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❌ 4 New Failures

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NEW FAILURES - The following jobs have failed:

• build (3.8) (gh)
• tests (3.10) / linux-job (gh)
• tests (3.8) / linux-job (gh)
• tests (3.9) / linux-job (gh)

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[facebook-github-bot]

This pull request was exported from Phabricator. Differential Revision: D46657526

[facebook-github-bot]

This pull request was exported from Phabricator. Differential Revision: D46657526

[facebook-github-bot]

This pull request was exported from Phabricator. Differential Revision: D46657526

[facebook-github-bot]

This pull request has been merged in cc16447.

[github-actions]

Hey @None.
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