Use a fake API key of length 32

[cbeauchesne]

Motivation

When the key is not length 32, the agent can stops itself :

https://github.com/DataDog/datadog-agent/blob/90535e90a71d31df934738c8b5738c806ffea8eb/pkg/api/security/security.go#L166
https://github.com/DataDog/system-tests-dashboard/actions/runs/12044074813/job/33580719639#step:49:86
https://datadoghq.atlassian.net/browse/APMSP-1600

Changes

Use a fake key with a length of 32 characters

Workflow

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Reviewer checklist

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