Bug#1071992: sqlmodel: please make this package compatible with SQL Alchemy 2.x

[Bastian Germann]

Control: notfound -1 sqlmodel/0.0.16-1
Control: fixed -1 sqlmodel/0.0.16-1
Control: found sqlmodel/0.0.8-6

The experimental version is actually already compatible with sqlalchemy 2.0.x.
Please move it to unstable.