[8.12](backport #37907) Fix hetzner and openstack tests by adding AWS_EC2_METADATA_DISABLED=true in ec2

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This is an automatic backport of pull request #37907 done by Mergify.

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• Start Time: 2024-02-14T16:13:18.051+0000

• Duration: 153 min 19 sec

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Test	Results
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Passed	28698
Skipped	2017
Total	30715

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