Wrap reads to cache with try except clauses

[abidsikder]

In practice, there seems to be some issues with the cache, that are not caught by the tests.
https://github.com/dClimate/etl-scripts/actions/runs/12622920508/job/35171365087
https://github.com/dClimate/etl-scripts/actions/runs/12609175178/job/35142444285
The cache errors seem to be fairly rare, but they do happen.

We should stop these errors with a try except clause until we can track down the true source.

[abidsikder]

Fixed in #16