Change PHPUnit link to avoid redirect to homepage
minor #4670 Change PHPUnit link to avoid redirect to homepage (xelaris)

This PR was merged into the 2.3 branch.

Discussion
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Change PHPUnit link to avoid redirect to homepage

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all
| Fixed tickets |

The previous link is redirected to the homepage of phpunit.de. The new one takes to the intended page.

Commits
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230d275 Change PHPUnit link to avoid redirect to homepage