fix: expose task secret fields

[YCK1130]

Because

• Some tasks need task-specific secret fields, which should only be included in the task.
• The current workarounds may harm UX significantly
  • Put it into settings and make it optional.
    • cons: Users might be confused by this irrelevant and non-functioning field when selecting the other tasks.
  • Use "oneOf" and make the setting to a dropdown list.
    • cons: Since we can neither set a default value to the "oneOf" field nor automatically choose the correct value with a specific task, users must choose which setting the task needs and select the correct one every time they create a new component. Thus, users must exert excessive effort to learn how this works.

This commit

• Expose task secret fields

Note

We need to adjust the logic of reading secret fields in pipeline-backend and frontend to reference the secret correctly.

1. What can we benefit from this solution?

Make the secret field more flexible.

2. Is there any concern or trade-off if we do this?

We need a thorough investigation and testing to make sure this won't affect existing schema and products.