<null> items added to end of carc file on save

[Elip100]

Describe the bug
When trying to save certain .carc files, BrawlCrate will add around 30 <null> items to the end. This only happens with certain files, and BrawlBox has the same issue.

To Reproduce
Steps to reproduce the behavior:

1. Download the Wii Sports game files
2. Edit files/US/RPCommon/local.carc
3. Save it
4. Re-open it

Expected behavior
Not adding <null> to the end

Screenshots

Desktop (please complete the following information):

• OS: Windows 11
• Version: Latest Canary version (happens with stable versions too)

Please attach any relevant files (if they do not have copyrighted content) you were working on. If the file is from a retail game, please instead name the game and the path to the file in the game's filesystem.

Wii Sports/files/US/RPCommon/local.carc among other files