Wrong error is displayed when uploading an invalid VPP Token

[PezHub]

Fleet version: 4.56

Web browser and operating system: any

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💥  Actual behavior

When uploading an invalid VPP token we get a generic error instead of "Invalid token. Please provide a valid content token from Apple Business Manager."

🧑‍💻  Steps to reproduce

1. Upload an invalid VPP Token (I took my existing one and broke it)
2. Note the generic error compared to the API response

🕯️ More info (optional)

🛠️ To fix It should match the one we see when uploading an invalid ABM Token

[PezHub]

QA Notes: Fix looks good!

[fleet-release]

Invalid token hides, Clearer message now guides, Ease in steps, it provides.