Spack version: 0.16.1 -> 0.16.2 (#25255)
Spack version: 0.16.1 -> 0.16.2 (#25255)

17473a08ff merged `v0.16.1` back into `develop` but somehow lost the version bump.  Fix it here.
LLNL/spack,LLNL/spack,LLNL/spack,LLNL/spack,LLNL/spack