Signing in GitHub Action fails with obscure error code

[Grannath]

Describe the bug
I need to sign an application built with the Rust framework Tauri. It has a GitHub Action that supports arbitrary commands for signing Windows executables. I've set it up to call this tool through a Powershell script.

I have tested the script locally and by calling it directly in a GitHub action. Both cases work fine. When I call the Azure CLI inside the Powershell script, it can log in fine as well. But the sign tool fails with an error -2147012894. This only happens when called by Tauri, not when I call the script directly.

For technical reasons, I have to use client id and client secret as environment variables for login. I cannot say if other methods work. I have confirmed that the variables are present and the values are valid.

Repro steps
I cannot point you to our internal repo, unfortunately. And I don't have a personal Azure account to set up a working example.

To set this up, build a Tauri application on GitHub using this action. Configure the app to use this sign tool as a custom sign command.

Expected behavior
Signing works also for Tauri applications.

Actual behavior
Signing fails with error -2147012894

Additional context
Logs from a run:

info: Sign.Core.ISigner[0]
      Submitting D:\a\my-app\my-app\target\x86_64-pc-windows-msvc\release\wix\x64\wix\WixUIExtension.dll for signing.
info: Sign.Core.ISigner[0]
      SignAsync called for D:\a\my-app\my-app\target\x86_64-pc-windows-msvc\release\wix\x64\wix\WixUIExtension.dll. Using C:\Users\runneradmin\AppData\Local\Temp\lu4c4tah.z2w\xqvyglkm.dll locally.
info: Sign.Core.IDataFormatSigner[0]
      Signing SignTool job with 1 files.
info: Sign.Core.IDataFormatSigner[0]
      Signing C:\Users\runneradmin\AppData\Local\Temp\lu4c4tah.z2w\xqvyglkm.dll.
fail: Sign.Core.IDataFormatSigner[0]
      Signing failed with error -2147012894.
info: Sign.Core.IDataFormatSigner[0]
      Performing attempt #2 of 3 attempts after 5 s.
info: Sign.Core.IDataFormatSigner[0]
      Signing C:\Users\runneradmin\AppData\Local\Temp\lu4c4tah.z2w\xqvyglkm.dll.
fail: Sign.Core.IDataFormatSigner[0]
      Signing failed with error -2147012894.
info: Sign.Core.IDataFormatSigner[0]
      Performing attempt #3 of 3 attempts after 11.1803398 s.
info: Sign.Core.IDataFormatSigner[0]
      Signing C:\Users\runneradmin\AppData\Local\Temp\lu4c4tah.z2w\xqvyglkm.dll.
fail: Sign.Core.IDataFormatSigner[0]
      Signing failed with error -2147012894.
fail: Sign.Core.IDataFormatSigner[0]
      Failed to sign. Attempts exceeded.
fail: Sign.Core.ISigner[0]
      Failed to sign. Attempts exceeded.