merge --dry-run raises error

[hamishcampbell]

$ kart --version
Kart v0.10.3.dev0+ci.2599.git2934f2b9, Copyright (c) Kart Contributors
» GDAL v3.2.0; PROJ v6.3.0
» PyGit2 v1.3.0; Libgit2 v1.1.0; Git v2.33.0
» SQLAlchemy v1.4.11; pysqlite3 v2.6.0/v3.31.1; SpatiaLite v5.0.0; Libpq v13.0.4
» SpatialIndex v1.9.3

merge help advertises the --dry-run option however running it raises an error:

$ kart merge my-edits --dry-run
Traceback (most recent call last):
  File "kart_cli.py", line 4, in <module>
  File "kart/cli.py", line 334, in entrypoint
  File "click/core.py", line 829, in __call__
  File "click/core.py", line 782, in main
  File "kart/cli.py", line 157, in invoke
  File "click/core.py", line 1259, in invoke
  File "click/core.py", line 1066, in invoke
  File "click/core.py", line 610, in invoke
  File "click/decorators.py", line 21, in new_func
  File "kart/merge.py", line 325, in merge
  File "kart/merge_util.py", line 713, in merge_status_to_text
TypeError: sequence item 1: expected str instance, tuple found
[19205] Failed to execute script kart_cli