feat(cli): add -i, --if-missing to detox build

[noomorph]

Description

This pull request adds -i, --if-missing CLI argument to detox build, so that you don't have sometimes to write extra checks in your CI build scripts whether the binary exists or not.

  -i, --if-missing     Execute the build command only if the app binary is missing.  [boolean]

➜  test git:(feat/lazy-build) npx detox build -c ios.sim.release --if-missing
detox[34137] INFO:  [build.js] Skipping build for "example" app...

In this pull request, I have …

For features/enhancements:

• I have added/updated the relevant references in the documentation files.