On 2022-03-22, the Glicko-2 algorithm was updated, with the following
line being added to the [Glicko web page][1]:
> This document has been revised on March 22, 2022, to replace a "<"
> with "<=" in item 4(b) of Step 5 (page 3).
See the [Glicko-2 document][2] for details.
Tests for this change are missing, as at the time of writing I couldn't
figure out a test that only made use of the current public interface.
[1]: http://glicko.net/glicko.html
[2]: http://glicko.net/glicko/glicko2.pdf
1. `rating`, `rating_deviation`, and `rating_interval` all omit the
possibility of receiving a `nil` as the second argument.
2. Writing out `Result.t()` results in `dialyzer` looking for
`Elixir.Result.t()`, instead of calling the local
`Elixir.Glicko.Result.t()`.
Change the cases where a `do:` is followed by a `mix format` mandated
line break, or if the expression following the `do:` would span multiple
lines anyway.
The only exception to the rule above is the first change in the
changeset, as this was done for the function style of `initial_rating`
to be consistent with `initial_rating_deviation`.
