#22303 fix mode representation git::tree ( in base 8 )

What does this MR do?

Present filemode in base 8 ( instead of 10 ).

The problem in #22303 (closed) was that the files are getting modes in base 10. ( e.g. for the symlink it's returning 40960 instead of 120000 ).

Are there points in the code the reviewer needs to double check?

The test is just to make sure that mode is returning the number in base 8. I didn't test specifically for symlink file return.

Why was this MR needed?

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Changelog entry added
• Documentation created/updated
• API support added
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

Closes #22303 (closed)