refactor(tvix/eval): clean up representation flip in bindings r/4999

When encountering a nested binding for the first time, cleanly flip
the representation to `Binding::Set` in `Binding::merge` before
proceeding with the actual merge.

This reduces the number of points where we have to deal with the (soon
to be slightly more complex) construction of the nested binding
representation.

Change-Id: Ifd43aac7b59ebd15a72c3ec512386a5bcf26ec13
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6802
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>

0 files changed, 0 insertions, 0 deletions