Fix license strings not being translated in metadata dropdown

[Arnei]

For example, "ALLRIGHTS" would be shown instead of "All rights reservered". This is fixed now, by hopefully properly parsing listproviders that put JSON arrays as their values instead of strings.

Fixes #559.

[github-actions]

This pull request is deployed at test.admin-interface.opencast.org/634/2024-06-05_12-01-34/ .
It might take a few minutes for it to become available.

[github-actions]

Use docker or podman to test this pull request locally.

Run test server using develop.opencast.org as backend:

podman run --rm -it -p 127.0.0.1:3000:3000 ghcr.io/opencast/opencast-admin-interface:pr-634

Specify a different backend like stable.opencast.org:

podman run --rm -it -p 127.0.0.1:3000:3000 -e PROXY_TARGET=https://stable.opencast.org ghcr.io/opencast/opencast-admin-interface:pr-634

It may take a few seconds for the interface to spin up.
It will then be available at http://127.0.0.1:3000.
For more options you can pass on to the proxy, take a look at the README.md.

[ziegenberg]

It Works!

[lkiesow]

Tested this with custom labels and that works as well:

list.name=LICENSES
…
CC0={"label":"EVENTS.LICENSE.CC0", "order":8, "selectable": true}
LK={"label":"Lars' license", "order":8, "selectable": true}
LK2=Lars' second license