fix: don't use deprecated nvim_err_writeln#36

idrilirdi wants to merge 1 commit intoGCBallesteros:mainGCBallesteros/jupytext.nvim:mainfrom

idrilirdi:use_nvim_echo_instead_of_deprecated_nvim_err_writelnidrilirdi/jupytext.nvim:use_nvim_echo_instead_of_deprecated_nvim_err_writelnCopy head branch name to clipboard