Would be nice to update the README with the julia version compatibility.

Actually, thinking about this a little more, now that we only test on 1.10 and above, should the Julia bounds in Project.toml be changed to reflect this?

We can still add back 1.6 in the tests - and that works fine I believe. Changing the julia version bound was problematic as it needed some changes on Taro.jl etc. but perhaps all of those are worth a quick refresh.

The right thing to do would be to add 1.6 as a julia version requirement and add min to the CI file to test it.