do_delete_users had two bugs:
1. Creating the replacement dummy users
with active=True
2. Creating the replacement dummy users with email domain set to
realm.uri, which may not be a valid email domain.
Prior commits fixed the bugs, and this migration fixes the pre-existing
objects.
This directory contains scripts that are used in building, managing,
testing, and other forms of work in a Zulip development environment.
Note that tools that are also useful in production belong in
scripts/ or should be Django management commands.
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