Update MySQL

[Vino-S]

Update MySQL version to 8.0

[DeniseColbert]

@lemon-ukgen can you remind us what we decided on this when Vino and I met with you a few weeks ago?

[lemon-ukgen]

I think it was: upgrade vervet to MySQL 8 and try a database update on it and see what breaks.

I don't think we formalise what test data is on vervet or how we refresh it. Regardless, it should help.

Depending on what it throws up, we may want to try again with a copy of the production data (though not on vervet, it would not cope)