Clean up builds from main branch that were not submitted for synthesis.

[vinoo-igem]

Somewhat similar to the failed synthesis builds, we also had builds that were not submitted for synthesis (TWIST's software rejected them, or they weren't TYPE IIS compatible), that I'll need to clean up. These can be seen in the synthesis tracker on main. What are thoughts on how to proceed with those: should they fall into the same scope as "unable to build," or a new description?

[jakebeal]

For now "unable to build" seems a reasonable catch-all category, since it doesn't give a reason that we were unable to build.