Update LiteDb to 5.0.17, add TestNet network warning, release 1.3.8 · atomex-me/atomex.client.desktop@26a1b13

The following actions uses node12 which is deprecated and will be forced to run on node16: actions/setup-node@v2, actions/setup-dotnet@v1, actions/download-artifact@v2, marvinpinto/action-automatic-releases@latest. For more info: https://github.blog/changelog/2023-06-13-github-actions-all-actions-will-run-on-node16-instead-of-node12-by-default/

The `set-output` command is deprecated and will be disabled soon. Please upgrade to using Environment Files. For more information see: https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/

The target framework 'net5.0' is out of support and will not receive security updates in the future. Please refer to https://aka.ms/dotnet-core-support for more information about the support policy.