download rendered job assets via `Optimus job explain` command

[Mryashbhardwaj]

Description Building upon https://github.com/odpf/optimus/issues/492 , add support for downloading rendered job assets.

Acceptance Criteria

• [ ] Download job assets with support for custom schedule time in specified local directory

Depends on : https://github.com/odpf/optimus/issues/492

Tech Details Post analysis Capture the details of the work needed to finish the task.

• [ ] Take inspiration from Optimus job render command

[Mryashbhardwaj]

handled in https://github.com/odpf/optimus/issues/577