repository: Refactor tests to support SHA256 object format
This MR refactors tests for the following RPCs to support the SHA256 object format:
- GetObjectDirectorySize
- RepositorySize
- FetchBundle
- CreateRepositoryFromSnapshot
Part of #5440 (closed).
This MR refactors tests for the following RPCs to support the SHA256 object format:
Part of #5440 (closed).