How to upgrade to Mautic 3.1?

[aerendir]

This is an old issue and there is already an open 3d for it:

Error Updating from Mautic 3.0 -->3.01

Dropping the foreign key doesn’t work. Once dropped, running a bin/console doctrine:schema:update --force tries to recreate the foreign key, but the query results in an error: An exception occurred while executing ‘ALTER TABLE *_oauth2_accesstokens ADD CONSTRAINT FK_E6019FAD19EB6921 FOREIGN KEY (client_id) REFERENCES *_oauth2_clients (id) ON DELETE CASCADE’: SQLSTATE[HY000]: General error: 3780 Referencing column ‘client_id’ and referenced column ‘id’ in foreign key constraint ‘FK_E6019FAD19…