Add SPID AspNetCore fixed package references

[cookesan]

Summary

• add the SPID AspNetCore 3.4.0 source tag and NuGet package references
• keep the NVD advisory reference for CVE-2025-24894

Validation

• confirmed the advisory aliases CVE-2025-24894 and affects SPID.AspNetCore.Authentication with fixed version 3.4.0
• confirmed the existing fix commit URL and the 3.4.0 source tag URL return HTTP 200
• confirmed the 3.3.0...3.4.0 comparison contains fix commit 093efa22
• confirmed NuGet lists SPID.AspNetCore.Authentication 3.4.0 and the 3.4.0 nuspec has the expected version and repository metadata
• confirmed the NuGet 3.4.0 package page resolves with HTTP 200
• confirmed NVD returns CVE-2025-24894 with status Deferred
• ran jq empty on the advisory JSON
• ran git diff --check