[CI] hombrew-cpp job is currently failing

### Describe the bug, including details regarding any error messages, version, and platform.

The [homebrew-cpp](https://github.com/ursacomputing/crossbow/actions/runs/24025581136/job/70063221579) job has been failing for the last ~50 days. It seems to be failing to apply a patch:

```
mv /private/tmp/homebrew-unpack-20260406-17114-sj9isa/ruby /private/tmp/apache-arrow-20260406-17114-sf340q/ruby
mv /private/tmp/homebrew-unpack-20260406-17114-sj9isa/testing /private/tmp/apache-arrow-20260406-17114-sf340q/testing
==> Patching
cp -p /Users/runner/Library/Caches/Homebrew/downloads/0d8fb0434846f5c75aa206478a5b387dc2e266585012d58c99e5e8f03fdfa8f2--03d40603d9f29a107a5cede0f94e6c0241cd6099.patch /private/tmp/apache-arrow--patch-20260406-17114-udvfjm/03d40603d9f29a107a5cede0f94e6c0241cd6099.patch
==> Applying 03d40603d9f29a107a5cede0f94e6c0241cd6099.patch
Error: Failure while executing; `patch -g 0 -f -p1` exited with 1. Here's the output:
patching file 'cpp/CMakeLists.txt'
1 out of 1 hunks failed--saving rejects to 'cpp/CMakeLists.txt.rej'
```

### Component(s)

Continuous Integration, Packaging

Start with the linked homebrew-cpp GitHub Actions job and inspect the patch application failure in cpp/CMakeLists.txt. Review the rejected hunk and the surrounding build configuration, then verify that the Homebrew job applies the patch and completes successfully.

Written by the indexing model from the issue text.