Change color of fa buttons in actions column to have a better contrast ratio

[rlucke]

Change color of fa buttons in actions column to have a better contrast ratio.

Fixes #637

[github-actions]

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[github-actions]

This pull request is deployed at test.admin-interface.opencast.org/651/2024-06-05_14-05-05/ .
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-651

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-651

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]

Note: I changed the title for a better release note entry, as they are auto-generated.

[ziegenberg]

@rlucke Are you sure this is a fix for #641 and not maybe #637? Can you verify please?

[rlucke]

You are absoluty right. Sorry for the mixup.