math/ess: Update to 26.05.0
- Licensed under GPL 3.0 for some time now
- Remove obsolete CONFLICTS_INSTALL=ess-emacs_*
- Jags mode has been moved to obsolete
- Add test target
Changelog: https://github.com/emacs-ess/ESS/blob/master/ChangeLog
Reported by: portscout, Repology