Common Data Model: support timeless vertex data

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (236f0d9) 92.67% compared to head (ee5eec8) 92.94%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #32 +/- ## ========================================== + Coverage 92.67% 92.94% +0.27% ========================================== Files 11 11 Lines 464 468 +4 ========================================== + Hits 430 435 +5 + Misses 34 33 -1 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.