Don't increment build number when using `--dry-run`

[rosen-kanev]

Bug report

When running the Chromatic CLI with --dry-run the build number is incremented. The counter seems to be incremented even if you don't wait for the command to exit and Ctrl^C it.

I stumbled upon it on the very first run of yarn chromatic --dry-run and then without the --dry-run flag. The deploy was successful and the Chromatic dashboard showed that I have only one build with the name "Build 2". When I opened it, there was an info section below the header with the text:
Build 2 is based on a commit without ancestor builds, which is unusual. Check out our build documentation

Probably low on your radar since it's pretty minor, but worth looking into it. IMO a dry run shouldn't produce side effects.