JsonException in GetAdminAccounts

[Freeesia]

Hello Mastonet Team,

I'm experiencing an issue with the GetAdminAccounts function in the Mastonet library when interacting with Mastodon. Here are the details:

1. Issue Description: When invoking the GetAdminAccounts method, a System.Text.Json.JsonException occurs.
2. Mastonet Version Affected: The issue is present in Mastonet version 3.1.0.
3. Mastodon Version: The error occurs with Mastodon version 4.2.3.
4. Temporary Solution: Downgrading Mastonet to version 2.3.1 seems to eliminate the exception.
5. Additional Details: A stack trace providing more insight into the issue can be found at this Sentry link: Sentry Stack Trace.

I would appreciate any help or guidance on resolving this issue. Thank you for your time and effort in maintaining this project.

Best regards.

[kescherCode]

The culprit for this issue is that certain fields in AdminAccounts should be nullable now, but aren't.