[platform] Ability to add volume mounts to connector pods

[thearchitector]

It would be incredibly useful to include the ability to add volume mounts to the connector pods automatically created by the airbyte worker, so any system or cluster-level files and/or configs that cannot be exposed via the connector config can be used.

A relatively trivial example of the usefulness of this would be for custom connectors that require shared data contained within a cluster's persistent volume.

I see no reason this wouldn't apply to environment variables as well for consistency, despite being also solvable via hidden connector config properties.