livecheck: remove test for livecheck_formulae

[nandahkrishna]

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This PR removes the network test for livecheck_formulae as it was failing sometimes. We will be adding network-related tests for livecheck later on in another PR after finding out why CI fails for GitHub URLs and now for other URLs too.

[MikeMcQuaid]

Thanks for the quick fix @nandahkrishna!