Selecting cells in a table with border=none results in some of the cell border to disappear

[michalbilik]

📝 Provide detailed reproduction steps (if any)

1. Checkout to maser and pull recent changes.
2. Open table manual test or docs.
3. Apply the none border style to the whole table.
4. Select some outer cells.

✔️ Expected result

The cell borders are visible, the same as in the current release: https://ckeditor.com/docs/ckeditor5/latest/features/tables/tables.html

❌ Actual result

Some cells' borders are invisible when selected:

https://github.com/user-attachments/assets/9d98cedf-fc83-430b-9ab8-e7411dc9bbca

❓ Possible solution

Most likely introduced in this PR: https://github.com/ckeditor/ckeditor5/pull/16880

📃 Other details

• Browser: All
• OS: macOS

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