Remove unused actions · planetarium/lib9c@27001c3

The following actions use a deprecated Node.js version and will be forced to run on node20: actions/setup-dotnet@v3. For more info: https://github.blog/changelog/2024-03-07-github-actions-all-actions-will-run-on-node20-instead-of-node16-by-default/

Possible null reference return.

Possible null reference return.

Possible null reference return.

Cannot convert null literal to non-nullable reference type.

Cannot convert null literal to non-nullable reference type.

Cannot convert null literal to non-nullable reference type.

Converting null literal or possible null value to non-nullable type.

Possible null reference return.

Possible null reference return.

Possible null reference return.

Provide feedback