GitLab

* Add all files

* Update masked_language_modeling.md

* fix mlm models

* fix conflicts

* fix conflicts

* fix copies

* Apply suggestions from code review
Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>
Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>

* Reduce seq_len and hidden_size in ModelTester

* remove output_attentions

* fix conflicts

* remove copied from statements

* Apply suggestions from code review
Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>

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Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>
Co-authored-by: amyeroberts <22614925+amyeroberts@users.noreply.github.com>