[Enterprise] "Preview unavailable" in attachments inside Test step field or Test Run actual result

Attachments inside Test step fields and Test Run actual result cannot be previewed after 1 day of being added to the field.

Steps to reproduce:

1. Create a Test step and save.
2. In the Attachments section, click the add button "+" and add an image.
3. Edit the step, select any text field (e.g. Data), open the attachments dropdown, add the image, and save the step.
4. After 1 day, open the Test Details and view the steps.

Expected result: The attachments in the Test steps are previewed correctly.

Actual result: The attachments in the Test steps have a warning "Preview unavailable".

Other situations:

• In a Test step field already with an image in its content, edit the field (e.g. add some text) and save the step.
• In a Test Run actual result, add an image (use the attachments dropdown in the editor, or paste or drop an image) and save.