test: use 127.0.0.1 explicitly instead of resolving localhost

[kruskall]

This is to avoid issues in CI with ipv6

Unblock #362

[ghost]

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• Start Time: 2023-01-18T08:03:11.762+0000

• Duration: 8 min 37 sec

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Test	Results
Failed	0
Passed	208
Skipped	2
Total	210

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