Upgrade Mysql 9.0 CI job to use 9.1 image

Seems to have a number of failures possibly from the update?

looks failures are random

What if we added a new job? Seems we are losing coverage on 8.3 and mysql 9. Think we should keep that and add one for 8.4 and mysql 9

I did it intentionally because Mysql 9.x is Innovation releases (9.0 is outdated) and latest PHP is 8.4 so oldest and newest combinations are covered

Moreover in related we can use better matrix 📌 [CI] Introduce a separate stage for unit tests Active

Okay I'll mark but still seems off to not have an 8.3 specific but could just be me.

The MR is still marked as a draft

Undrafted MR

Committed e444db8 and pushed to 11.x. Thanks!