hydra: revert 24180

Dependencies

• [2] YQWH4POV * Simplify.
• [*] T4LLYESZ * Nix expression for building Hydra.

Change contents

• edit in release.nix at line 62
  [2.2994]

  [2.2994]
  + --set HYDRA_HOME $out/libexec/hydra \