CompatHelper: bump compat for "Optim" to "1.2"

[github-actions[bot]]

This pull request changes the compat entry for the Optim package from 0.20, 0.21, 0.22 to 0.20, 0.21, 0.22, 1.2.

This keeps the compat entries for earlier versions.

Note: I have not tested your package with this new compat entry. It is your responsibility to make sure that your package tests pass before you merge this pull request.