add await when invoking schemaVersion

[barakcoh]

Check List

• [X ] Tests has been run in packages where changes made if available
• [ X] Linter has been run for changed code
• Tests for the changes have been added if not covered yet
• Docs have been added / updated if required

Description of Changes Made (if issue reference is not provided)

Add support for cases where schemaVersion needs to be async, e.g. fetching the version from remote storage

[paveltiunov]

@barakcoh Hey Barak! Just briefly checked code usage and it seems it probably not so easy as I thought before. schemaVersion property set in CubejsServerCore.getCompilerApi() and it isn't async. Good new is probably we can make it async.

[barakcoh]

hi @paveltiunov ! should I just add another await at https://github.com/cube-js/cube.js/blob/af07865ae2d3c11836ab5e01f17e97c3b2d5d662/packages/cubejs-server-core/core/index.js#L383?

[paveltiunov]

@barakcoh Yeah. Right. And make it async.

[paveltiunov]

@barakcoh Just checked usages more thoroughly and it seems we're safe to revert all changes to index.js as only await is in fact required. So your initial change was correct.

[barakcoh]

thanks @paveltiunov i'll push a reverse commit