minor #48 add build jobs for PHP 7.3 and 7.4 (xabbuh)
minor #48 add build jobs for PHP 7.3 and 7.4 (xabbuh)

This PR was merged into the 2.x branch.

Discussion
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add build jobs for PHP 7.3 and 7.4

Commits
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2292ba6 add build jobs for PHP 7.3 and 7.4

php-xapi/serializer