Missing spacing in output

[arxanas]

Observe this output:

$ git stack
master cleanup(bug_report): add a comment about explicit listing of fields
├─┐
│ ⌽ no-dedup (pushed) feat(move): add `--no-deduplicate-commits` option
├─┐
│ ⌽ d5736d7 temp: work on moving individual commits
│ ⌽ move-individual-commits (pushed) temp: more move individual commits
├─┐
│ ⌽ 29e0946 build: remove dependency on `git-revset`
│ ⌽ a85da5f build: run `cargo upgrade`
│ ⌽ dependabot (pushed) build: add `dependabot.yml`
⌽ 62128e9 fix(effects): fix for often-updated nested operations
⌽ 315d64b fix(rewrite): use existing progress reporting
⌽ progress (pushed) effects: strip ANSI codes from sub-operation output

I think there should be an extra semi-blank line for the last branch, like this:

[tw-mbp-wkhan git-branchless (master)]% git stack
master cleanup(bug_report): add a comment about explicit listing of fields
├─┐
│ ⌽ no-dedup (pushed) feat(move): add `--no-deduplicate-commits` option
├─┐
│ ⌽ d5736d7 temp: work on moving individual commits
│ ⌽ move-individual-commits (pushed) temp: more move individual commits
├─┐
│ ⌽ 29e0946 build: remove dependency on `git-revset`
│ ⌽ a85da5f build: run `cargo upgrade`
│ ⌽ dependabot (pushed) build: add `dependabot.yml`
│
⌽ 62128e9 fix(effects): fix for often-updated nested operations
⌽ 315d64b fix(rewrite): use existing progress reporting
⌽ progress (pushed) effects: strip ANSI codes from sub-operation output

Otherwise, all but the last branch have a contentless line preceding them.

[epage]

Seems reasonable. Created #206

[epage]

v0.7.1 is now released with this fixed