Http source used instead of https

[pwasiewicz]

Describe the bug

I have BaGet setup as https:
https://nuget.mycorporation.com/v3/index.json

It is used in nuget.config:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
    <packageSources>
        <add key="My Corp source" value="https://nuget.mycorporation.com/v3/index.json" protocolVersion="3"  />
    </packageSources>
</configuration>

When using newest .net core 10 sdk, I can't download package as nuget manager is saying that my package source is not secure.
---> NuGet.Protocol.HttpSourceException: You are using a NuGet source 'https://nuget.mycorporation.com/v3/index.json' that contains an 'HTTP' service index resource endpoint: 'http://nuget.mycorporation.com/v3/registration/some-package/index.json'. This is insecure and not recommended. To allow HTTP resources, you must explicitly set 'allowInsecureConnections' to true in your NuGet.Config file. For more information, visit https://aka.ms/nuget-https-everywhere.

My index.json endpoint uses http as id package. Is that a root cause?

Http to https redirect is enabled on proxy level.

How can I force using https registration sources in baget?

[Ccheers]

same here