cli: don't ignore diff --tool=:builtin, report error
#7
| Job | Run time |
|---|---|
| 4m 14s | |
| 4m 36s | |
| 8m 50s |
diff --tool=:builtin, report error
#7
| Job | Run time |
|---|---|
| 4m 14s | |
| 4m 36s | |
| 8m 50s |