When using a start date before the first commit to a repo, we should
include the repo's entire history (up to the end date) in our totals.
Instead, we were using a range like "..{upper_version}", which in Git
revision-range syntax means the start of the range is HEAD -- so the
range was empty.
Fix that by leaving out the ".." when we want no left endpoint.
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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