Automate updating exceptions.csv and metadata

[FrancescaMancini]

These steps should be automatically performed when new outputs are transferred to the object store

[DylanCarbone]

For context, this is from issue #90 :

We need to add a list (called exceptions.csv) to the object store to allow createMetadata to identify those model runs that should not be used for indicator production (for now only those that include LERC data). This list needs to be updated every time we add outputs and data to the object store that should not be used in other projects.