LibGit2SharpException: could not find appropriate mechanism for credentials

Reproduction steps

Upgraded from v0.26.2 to v0.30.0, had compilation issues. Fair enough, we were quite out of date.
We changed the credentials provider as this was now located in the FetchOptions (see #2065).
I even tried setting the ProxyOptions.ProxyType to None as that was now Auto by default.

Has there anything changed regarding credentials between those versions? I didn't immediately spotted something on the releases/changes page.

Expected behavior

Everything keeps working as normal.

Actual behavior

Exception is thrown when trying to clone a repository:
LibGit2Sharp.LibGit2SharpException: could not find appropriate mechanism for credentials at LibGit2Sharp.Core.Ensure.HandleError(Int32 result) in /_/LibGit2Sharp/Core/Ensure.cs:line 136 at LibGit2Sharp.Core.Proxy.git_clone(String url, String workdir, GitCloneOptions& opts) in /_/LibGit2Sharp/Core/Proxy.cs:line 278 at LibGit2Sharp.Repository.Clone(String sourceUrl, String workdirPath, CloneOptions options) in /_/LibGit2Sharp/Repository.cs:line 810

Version of LibGit2Sharp (release number or SHA1)

v0.30.0

Operating system(s) tested; .NET runtime tested

Windows 11
.NET Framework 4.8

Reproduziere den Clone-Fehler unter Windows 11 mit LibGit2Sharp v0.30.0 und vergleiche die Einrichtung der Anmeldedaten mit v0.26.2, ausgehend von CloneOptions, FetchOptions und ProxyOptions. Untersuche die im Bericht genannten Pfade in Core/Ensure.cs, Core/Proxy.cs und Repository.cs und verwende anschließend #2065 und die Änderungen des Releases, um festzustellen, ob sich das Verhalten der Anmeldedaten geändert hat und wie ein korrigiertes Ergebnis aussehen sollte.