feat(tvix/derivation): derive Default for Derivation r/5623

Some of the fields in a Derivation struct stay empty, and manually
creating BTreeMap or vec for it is annoying.

Derive Default instead, so we can use the defaults instead of writing
more by hand.

Change-Id: I5d41b4b55c8187cb101eb4266451a470008e0067
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7788
Reviewed-by: tazjin <tazjin@tvl.su>
Autosubmit: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI

0 files changed, 0 insertions, 0 deletions