[Data] Change type of DataContext.retried_io_errors from tuple to list

[bveeramani]

Why are these changes needed?

Users often want to add to the list of retried IO errors. Currently, you need to do something like this because the default list isn't mutable:

retried_io_errors = list(DataContext.get_current().retried_io_errors)
retried_io_errors.append("ACCESS_DENIED")
DataContext.get_current().retried_io_errors

To improve the usability, this PR changes the type to a mutable list:

 DataContext.get_current().retried_io_errors.append("ACCESS_DENIED")
```

Mutable default arguments is generally a bad practice, but `DataContext` is a singleton, so this shouldn't be a big issue.

## Related issue number

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