The piece of code that is removed in this PR predates environment views.
Spack would symlink build logs in `<env>/.spack-env/logs/*`, but this is
redundant because:
1. Views already add `<prefix>/.spack` (and there's logic there to avoid
clashes)
2. The code was broken anyways: it would only symlink the logs of
environment roots, not their deps, even if they were just built.
If users disable views, I'm pretty sure they're not waiting for
`.spack-env/logs` either. So, imo we can delete this code, and it was
probably overlooked in the past.
00c4efb96e