Add CLI flag to only build specific projects

[kejistan]

When running the compiler with a config that contains multiple projects all projects are always built. This is definitely a sane default, but it'd be nice to be able to only build a subset. The use case I'm specifically thinking about is with the query persister in a deploy pipeline: if I can run the compiler against only a single project I can also persist just the queries in that single project (rather than all the projects).