refactor(tvix/castore/fs): use consistent span field name for handle r/7916

Use rq.handle in `release` too, and remove interpolating it into the
log message itself.

Also update the comment, we don't get ownership, just simply drop, and
change the level to warn!, as suggested in cl/11425.

Change-Id: If4e6cff6d8b580671b1548ae3862851db4af6694
Reviewed-on: https://cl.tvl.fyi/c/depot/+/11427
Reviewed-by: raitobezarius <tvl@lahfa.xyz>
Tested-by: BuildkiteCI
Autosubmit: flokli <flokli@flokli.de>

0 files changed, 0 insertions, 0 deletions