minor #3616 Add 8.1 in tests (fabpot)
minor #3616 Add 8.1 in tests (fabpot)

This PR was merged into the 2.x branch.

Discussion
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Add 8.1 in tests

Commits
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3deeb0b2 Add 8.1 in tests

twigphp/Twig,twigphp/Twig,twigphp/Twig