[C2] Fix "ROLE_" inconsistencies in the database

[ywarnier]

For some reason, we ended up with some roles (as in user.roles JSON field) that have a "ROLE_" prefix, and others that don't, even for the same role (like ROLE_GLOBAL_ADMIN vs GLOBAL_ADMIN).

Clean this up by ensuring all roles in the user table are using the "ROLE_" prefix.

[christianbeeznest]

It is checked with this commit fe64a03

Thanks for confirmation.

[ywarnier]

Tested and approved. Thanks!