[ci-jobs] Add disableHpos test environment variable

[adimoldovan]

Submission Review Guidelines:

• I have followed the WooCommerce Contributing Guidelines and the WordPress Coding Standards.
• I have checked to ensure there aren't other open Pull Requests for the same update/change.
• I have reviewed my code for security best practices.

Changes proposed in this Pull Request:

This PR fixes 2 problems:

1. The DISABLE_HPOS env variable is not set in CI and the disabling of the feature was not happening in the test environment setup script.
2. Even with the above fixed, if the setup script disables the feature, after the first login the feature is reset to the default.

The fix:

1. Properly set the environment variable via the ci-jobs utility.
2. Toggle the feature via the global setup after the first login.

I replaced the global setup logic of enabling the feature (ENABLE_HPOS) with disabling it (DISABLE_HPOS) as it makes more sense to me to be explicit about the action that changes the default state.

How to test the changes in this Pull Request:

Using the WooCommerce Testing Instructions Guide, include your detailed testing instructions:

Tested with this run where the HPOS disabled tests were set to run on pull_request. The DISABLE_HPOS=1 is correctly set in the env, and the global setup disables the feature.

[github-actions]

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[github-actions]

Hi , @woocommerce/vortex

Apart from reviewing the code changes, please make sure to review the testing instructions as well.

You can follow this guide to find out what good testing instructions should look like:
https://github.com/woocommerce/woocommerce/wiki/Writing-high-quality-testing-instructions

[rrennick]

Nice work