minor #7337 Remove test (excluded in phpunit.xml.dist) and fixtures because Filte… (michaelKaefer)

This PR was merged into the 4.x branch.

Discussion
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Remove test (excluded in phpunit.xml.dist) and fixtures because Filte…

…rRegistry does not exist anymore

Commit that deleted `FilterRegistry`: 7112595

Commits
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5dd413b Remove test (excluded in phpunit.xml.dist) and fixtures because FilterRegistry does not exist anymore

Author: javiereguiluz