Revert "Add cabal exec"

This reverts commit 99d912d321a750739475412c4510075675b2b91b.

Looks like Johan managed to botch a merge somehow, see #1786. Or maybe that was
a bug on the GitHub side.

(cherry picked from commit d10d67ccf2496fce5f6e38345f6338c816d0e4f3)