Use caret versioning for workspaces

[ggetz]

To avoid issues like #11278 in the future, we should move to caret versioning for the internal @cesium workspace dependencies.

It's too easy to publish a release with this version issue, so at the minimum some automated tooling needs to be in place to verify any workspace version updates.

[ggetz]

To update, we'll need to confirm the scripts (postversion) in gulpfile.js write out the version along with the caret.

It'd be great to have a smokescreen test running in CI like Specs/test.mjs (run in .travis/verify.js) to ensure all the version are woking as well.