[Graphbolt][Cleanup] Remove old code after seeds refactor

[BowenYao18]

🔨Work Item

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Project tracker: https://github.com/orgs/dmlc/projects/2

Description

The Datasets that have no "-seeds" BuiltinDataset in the onDiskDataset.py that are not used anymore. We need to remove them.

Moreover, any code that needs to be removed after the seeds refactoring needs to be considered.

Depending work items or issues