Encoding.default_external was chosen over
Encoding.default_internal because File.read is
returning Encoding.default_external, therefore
we should align with it. Alternatively, we could
force both of them to be Encoding.default_internal.

However, ideally this should be determined by different
projects. For example, some projects might want to use
an encoding different to what GitLab is using.

This might not happen soon though.

Closes #27052