Remove version assertion from chart unit tests

Follow up from !175 (comment 496556240)

We assert that the version in Chart.yaml matches a fixed version in the test file. This just adds friction for contributors and should be removed.

mentioned in commit b638ffde

mentioned in merge request !208 (merged)

assigned to @hfyngvason

changed milestone to %14.2

mentioned in commit 6e33b5ec

closed with merge request !208 (merged)