Original MR 21

This is merely an older version of the spack file to fix an issue where the older version of acts somehow does not correctly build anymore with the new package file. This should be removed when we upgrade acts.

spack/packages/acts/README.md

+This is merely an older version of the spack file to fix an issue where the older version
+of acts somehow does not correctly build anymore with the new package file. This should be
+removed when we upgrade acts.