fix(ci): Fix yaml generation script

[sentrivana]

The generation script -- when run with --fail-on-changes -- was supposed to raise an error if it detected that the integration test YAML files have changed but haven't been committed. The check is based on a hash of the contents of the YAML files, but there was a typo in the file names to consider (integration -> integrations), so it wasn't actually looking at any files and was always trivially true.

Now it'll properly complain if changes are made to tox.ini or to some of the constants in the splitting script that result in new YAML files, but those are not part of the commit.

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