migrated all possible assets from GCP to repo

[ethantang-db]

What does this PR do?

After the deletion of mosaic's assets on GCS, this PR is an attempt to restore most of the assets that were removed.

Some assets were not recovered though as archive never managed to store them. These includes

https://storage.googleapis.com/docs.mosaicml.com/images/methods/sam.png
https://storage.googleapis.com/docs.mosaicml.com/images/methods/layer-freezing.png
https://storage.googleapis.com/docs.mosaicml.com/images/methods/gated_linear_units.png
https://storage.googleapis.com/docs.mosaicml.com/images/methods/swa.png
https://storage.googleapis.com/docs.mosaicml.com/images/tutorials/launch_instance.png
https://storage.googleapis.com/docs.mosaicml.com/images/tutorials/configure_ebs.png
https://storage.googleapis.com/docs.mosaicml.com/images/profiler/analyzing_traces-trainer_events.png
https://storage.googleapis.com/docs.mosaicml.com/images/profiler/analyzing_traces-dataloader.png
https://storage.googleapis.com/docs.mosaicml.com/images/profiler/analyzing_traces-system_metrics.png
https://storage.googleapis.com/docs.mosaicml.com/images/profiler/analyzing_traces-torch.png
https://storage.googleapis.com/docs.mosaicml.com/images/profiler/analyzing_traces-composer.png
https://storage.googleapis.com/docs.mosaicml.com/images/profiler/analying_traces-example_pre.png
https://storage.googleapis.com/docs.mosaicml.com/images/profiler/analyzing_traces-example_post.png
https://storage.googleapis.com/docs.mosaicml.com/images/training_loop.png

Pour one out for those image asset homies

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