Update generic tests for changes in AbstractAlgebra.

[wbhart]

This probably shouldn't be strictly necessary, but the Nemo generic tests were calling the internal AbstractAlgebra functions which changed. Therefore this PR is necessary to adjust for the changes over there.

This probably has a bearing on #909

[wbhart]

I'm actually not sure why the CI fails here. I guess it's using a released version of AbstractAlgebra which doesn't contain the new function.

Should I update the version number in Nemo's compat with this PR?

[thofma]

The tests are using AbstractAlgebra v0.11.1, which was tagged yesterday or the day before.

[rfourquet]

I guess it's using a released version of AbstractAlgebra which doesn't contain the new function.

Indeed, the latest AA release is v0.11.1 and is used in the tests, but can_solve_with_solution_fflu is only present on the master branch. So this PR will have to wait for a new AA release, and then Nemo will have to depend on AA v0.11.2. But as it's just test code with only a couple of lines, I rather suggest to make the the use of the functions conditional. I will comment inline.

[wbhart]

There's also can_solve_with_solution_lu which only exists in master. That's why the tests still fail.

[rfourquet]

There's also can_solve_with_solution_lu which only exists in master. That's why the tests still fail.

Yes I just updated it, I guess tests should pass now.

[wbhart]

The failure is unrelated and can be ignored.