Upload transcript progress bar breaks when processing two or more files

[allishultes]

Describe the bug
A clear and concise description of what the bug is.
When multiple files are uploaded for transcription, the progress bars jump and don't render properly.

To Reproduce
Steps to reproduce the behaviour:

1. Go to a project in DPE
2. Upload two longer media files, one after another
3. Watch the progress bar sputter

Expected behaviour
A clear and concise description of what you expected to happen.
The progress bars should render appropriately for each upload.

Screenshots
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Additional context
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