Cleanup get_local_ip in global conftest

[epenet]

Proposed change

The function it was overriding was removed in #58669 (October 2021)
cc @chemelli74 / @bdraco / @balloob

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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Additional information

• This PR fixes or closes issue: fixes #
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[chemelli74]

Thx @epenet !