Video Editor tests can't upload translations on Firefox 57

Description

Reference for Bok Choy upgrade process: https://openedx.atlassian.net/wiki/spaces/TE/pages/567083109/Firefox+57+upgrade+for+Bok+Choy+tests

Description: As part of the Firefox upgrade on Jenkins, the following tests are failing, and need to be fixed

Error Msg:

Stack Trace:

Link to failing build: https://build.testeng.edx.org/job/edx-platform-test-subset/1100578/

Tests Impacted:

acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_cannot_upload_sjson_translation
acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_replace_translation_w_save
acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_replace_translation_wo_save
acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_select_language_twice
acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_simplified_and_traditional_chinese_transcripts_uploading
acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_table_of_contents
acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_translation_upload_remove_upload
acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_translations_clearing_works_w_saving
acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_translations_clearing_works_wo_saving
acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_translations_download_works_w_saving
acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_translations_download_works_wo_saving
acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_translations_remove_works_w_saving
acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_translations_remove_works_wo_saving
acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_translations_uploading
acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_upload_large_transcript
acceptance.tests.video.test_studio_video_editor.VideoEditorTest.test_upload_transcript_with_BOM

Steps to Reproduce

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Current Behavior

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Expected Behavior

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Reason for Variance

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Release Notes

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User Impact Summary

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Assignee

Stuart Young

Reporter

Stuart Young

Reach

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Impact

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Platform Area

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Customer

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Partner Manager

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URL

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Contributor Name

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Groups with Read-Only Access

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Actual Points

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Category of Work

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Platform Map Area (Levels 1 & 2)

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Platform Map Area (Levels 3 & 4)

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Sprint

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Priority

CAT-3
Configure