Upgrade toybox to 23fc1ecab1b49e3dfd681882946c6729adb78da6

This project was upgraded with external_updater.
Usage: tools/external_updater/updater.sh update toybox
For more info, check https://cs.android.com/android/platform/superproject/+/master:tools/external_updater/README.md

Test: TreeHugger
Change-Id: I937e8848d57a84506d8342119222264332101fad