Script to find json mappings

[fm3]

URL of deployed dev instance (used for testing):

• https://___.webknossos.xyz

Steps to test:

• abc

TODOs:

• [ ] ...

Issues:

• fixes #

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(Please delete unneeded items, merge only when none are left open)

• [ ] Updated changelog
• [ ] Updated migration guide if applicable
• [ ] Updated documentation if applicable
• [ ] Adapted wk-libs python client if relevant API parts change
• [ ] Removed dev-only changes like prints and application.conf edits
• [ ] Considered common edge cases
• [ ] Needs datastore update after deployment