From here:
https://www.phpbb.com/community/viewtopic.php?f=461&t=2390376

There are issues with the dbal when installing an extension. Here are two example extensions that previously installed and worked fine on 3.1.9

The Top Five extension
-https://www.phpbb.com/customise/db/extension/topfiveext/-

which produces this error

Stop Forum Spam
https://www.phpbb.com/customise/db/extension/phpbb_3.1_stop_forum_spam/

produces this error

Deleting the db folder from 3.1.10 and placing the one from 3.1.9 corrects the issues.