fix the bug when truncate_side==left

[rongruosong]

PR types

Bug fixes

PR changes

Others

Description

在MLMPromptTokenizer中，当 self.tokenizer.truncate_side == 'left'是True，函数_create_max_lengths_from_do_truncate 的结果包含None，input_ids = orig_input_ids[index][-max_lengths[index] :]会造成：TypeError: bad operand type for unary -: 'NoneType'

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[github-actions]

This Pull Request is stale because it has been open for 60 days with no activity. 当前Pull Request 60天内无活动，被标记为stale。

[github-actions]

This Pull Request is stale because it has been open for 60 days with no activity. 当前Pull Request 60天内无活动，被标记为stale。

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[github-actions]

This Pull Request is stale because it has been open for 60 days with no activity. 当前Pull Request 60天内无活动，被标记为stale。

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Automatically closed by Paddle-bot.