Standardize artifact_type typing in _get_v1_dataset, _upload_v1_dataset and _upload_benchmark

[mercuryseries]

Context

In the _get_v1_dataset, _upload_v1_dataset, and _upload_benchmark methods, the artifact_type parameter is typed as ArtifactSubtype, but in many instances, we pass a string instead. This inconsistency can lead to confusion or potential issues.

Description

To improve code consistency and maintainability, the artifact_type parameter should be standardized to consistently use ArtifactSubtype in _get_v1_dataset, _upload_v1_dataset, and _upload_benchmark methods. This will involve refactoring any instances where a string is passed instead of ArtifactSubtype. Additionally, any dependencies, tests, or documentation related to these methods should be reviewed to ensure compatibility and stability.

Acceptance Criteria

• The artifact_type parameter is consistently typed as ArtifactSubtype in _get_v1_dataset, _upload_v1_dataset, and _upload_benchmark.
• All instances where a string is passed as artifact_type are updated to ArtifactSubtype.
• Code and comments are updated to reflect this change.
• All related tests pass without regression.

Links

• Feature: Download for V2 datasets #210 (comment)