Refactor logging of `rank_zero_seed`

[abhi-mosaic]

This line is logging the rank_zero_seed as if it is time series data, but it's a static value that is only configured once. It looks very out of place in logger backends like WandB. I think rank_zero_seed should be stored in config somewhere but not logged as time series.

This can be done by either promoting it to the TrainerHparams, or creating a new update_config() function that LoggerDestinations have to implement.

Also a UX bug -- if each rank is logging in distributed training, then the seed stored in each rank's config is now incorrect because Trainer has overridden it to be rank_zero_seed + rank. Are there any other codepaths we are overriding values in the config?

https://github.com/mosaicml/composer/blob/204129b810ce71d4089781b6ee2bef9f0b2703f1/composer/trainer/trainer.py#L873

[abhi-mosaic]

This is what WandB looks like right now:

[ravi-mosaicml]

I like the idea of implementing update_config in the logger destinations, as different loggers may want to store config differently.

[eracah]

Closed by PR #1416