Fix missing spack.compiler import (#8240)
Fix missing spack.compiler import (#8240)

Fixes: #8258

#8090 altered import behavior so that import spack no longer
provides access to many other Spack modules. This addresses
a case which depended on the prior behavior and was not
updated as part of #8090. This particular import error only
came up when users were setting compiler flags on specs.

See also: #8194
krafczyk/spack,LLNL/spack,mfherbst/spack,tmerrick1/spack,matthiasdiener/spack,krafczyk/spack,krafczyk/spack,matthiasdiener/spack,iulian787/spack,iulian787/spack,mfherbst/spack,iulian787/spack,LLNL/spack,krafczyk/spack,tmerrick1/spack,LLNL/spack,tmerrick1/spack,mfherbst/spack,matthiasdiener/spack,iulian787/spack,iulian787/spack,mfherbst/spack,krafczyk/spack,mfherbst/spack,matthiasdiener/spack,matthiasdiener/spack,LLNL/spack,tmerrick1/spack,LLNL/spack,tmerrick1/spack