Revert "Explicitly exit with status "1" for create and drop failures"

This reverts commit 22f80ae57b26907f662b7fd50a7270a6381e527e.

See
https://github.com/rails/rails/commit/22f80ae57b26907f662b7fd50a7270a6381e527e#commitcomment-4640676

Conflicts:
	activerecord/CHANGELOG.md
Revert "Properly require database tasks so we have access to the raised constant"

This reverts commit fbcd46b1a0d255a34d29caa77bbd31c287446333.

This is not needed anymore. See 7280965