Use powershell and Microsoft Managed Service account to add file to sharepoint online

Hello,

we have a powershell script generating files (csv). Simple.

We want these files to be sent to a sharepoint online site. Simple

As a best practice, the script is run automatically using a Microsoft Managed Service Account (MSA or gMSA).

How can we send these files to this site without providing a user's credentials?

We would like to provide write access to the MSA account but since this is no an AD user I don't seem to be able to choose this when providing access to my site.

Any help would be appreciated.

Thank you