Running tests on x86 seems to fail (Conda.jl/RCall.jl issue)

See https://github.com/frankier/ComputerAdaptiveTesting.jl/actions/runs/3052463740/jobs/4921878850

The error is:

```
caused by: could not load library "/usr/lib/R/lib/libR.so"
/usr/lib/R/lib/libR.so: wrong ELF class: ELFCLASS64
```

So somehow we are ending up with a 64 bit R on 32 bit.