Reduce the amount of terms shown in attributes page

[Konamiman]

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Changes proposed in this Pull Request:

As mentioned in #26539 (comment), the product attributes page lists all the existing product attributes together with all the existing terms for each one. In order to improve the performance of that page, the number of terms shown for each attribute is now limited to 100 by default, but this value can be customized by using the newly introduced woocommerce_max_terms_displayed_in_attributes_page filter.

Additionally, the get_terms( $taxonomy) call is changed into get_terms(['taxonomy' => $taxonomy, 'fields' => 'names']) so that only term names are retrieved instead of the full set of terms information.

The UI is adjusted accordingly as well. This is how it looks like when the filter returns 3:

And this is with the filter returning zero:

How to test the changes in this Pull Request:

1. Add the following snippet: add_filter('woocommerce_max_terms_displayed_in_attributes_page', function() {return 3;});
2. Create attributes with 0, 1, 2, 3, 4 and 10 terms, and verify that the attributes list displays as in the first screenshot above.
3. Change the filter to return zero, and verify that the attributes list displays as in the second screenshot above.

Other information:

• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes, as applicable?
• Have you successfully run tests with your changes locally?
• Have you created a changelog file for each project being changed, ie pnpm changelog add --filter=<project>?

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[github-actions]

Test Results Summary

Commit SHA: f042e28

Test 🧪	Passed ✅	Failed 🚨	Broken 🚧	Skipped ⏭️	Unknown ❔	Total 📊	Duration ⏱️
API Tests	115	0	0	2	0	117	0m 41s
E2E Tests	185	0	0	1	0	186	14m 4s

To view the full API test report, click here.
To view the full E2E test report, click here.
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[vedanshujain]

LGTM! I think you need to rebase from trunk to get tests to pass.

[github-actions]

Hi @Konamiman, thanks for merging this pull request. Please take a look at these follow-up tasks you may need to perform:

• Add the release: add testing instructions label