fix: remove non-existing user from CODEOWNERS

[jeertmans]

Describe your change:

Removes user @mateuszz0000 that does not exist, or seems to have been renamed to @l3str4nge.

According to the git blame, @l3str4nge is the one that originally updated this file. By reading the comments in #3280, it seems like @mateuszz0000 was changed to @l3str4nge.

I don't think it is a security issue, if I read correctly the "About code owners" guide, but I guess it's worth keeping thinks up to date. @l3str4nge does not seem to be active on this repo anymore, but I can update the PR to change @mateuszz0000 with @l3str4nge.

Checklist:

• I have read CONTRIBUTING.md.
• This pull request is all my own work -- I have not plagiarized.
• I know that pull requests will not be merged if they fail the automated tests.
• This PR only changes one algorithm file. To ease review, please open separate PRs for separate algorithms.
• All new Python files are placed inside an existing directory.
• All filenames are in all lowercase characters with no spaces or dashes.
• All functions and variable names follow Python naming conventions.
• All function parameters and return values are annotated with Python type hints.
• All functions have doctests that pass the automated testing.
• All new algorithms have a URL in its comments that points to Uncyclopedia or other similar explanation.
• If this pull request resolves one or more open issues then the commit message contains Fixes: #{$ISSUE_NO}.