FilamentManager 1.7.1 and Print Job History

[rmilyard]

Describe the bug
Since updating to this version I keep getting this when start OctoPrint.

Optional plugins
To get the real power of the Print Job History - Plugin you need the following plugins installed/enabled:

FilamentManager (missing)
disable optional plugin check Close

Steps to reproduce

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Expected behavior
A clear and concise description of what you expected to happen.

Did the same happen when all other 3rd party plugins are disabled?
If not which plugin is causing the issue?

Log file
Drag and drop the octoprint.log here.

Screenshots
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Additional context
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[moong8te]

Issue also reported here with more details from different users:
#38