CI: remove homebrew autoupdate deactivation from CircleCI

[onetechnical]

Summary

Nightly tests have been failing due to homebrew installation. We're attempting to fix this by not disabling homebrew upgrades.

The error we were getting was this:

Error: Failure while executing; `/usr/bin/env /opt/homebrew/Library/Homebrew/shims/shared/curl --disable --cookie /dev/null --globoff --show-error --user-agent Homebrew/4.0.3\ \(Macintosh\;\ arm64\ Mac\ OS\ X\ 12.6.3\)\ curl/7.79.1 --header Accept-Language:\ en --fail --progress-bar --retry 3 --location --remote-time --output /Users/distiller/Library/Caches/Homebrew/Formula/libarchive.rb https://raw.githubusercontent.com/Homebrew/homebrew-core/da26dd20d93fea974312a0177989178f0a28d211/Formula/libarchive.rb` exited with 22. Here's the output:
curl: (22) The requested URL returned error: 404

The raw github URL here has a typo - it is missing lib/ in the path. Homebrew itself needs to be updated to fix this problem.

We specifically avoided updating homebrew in #2608 as a build optimization, but as the default is no longer working and we aren't pinning the dependencies here, we should restore the update.

Test Plan

Try to run nightly tests on this branch.