Swap `MappedLocalTime` and `LocalResult` type alias

[pitdicker]

In #1501 I thought renaming LocalResult to MappedLocalTime would be entirely without consequences as long as there is a type alias with the old name. Turns out there is one case where a type alias behaves differently :disappointed:. You can't import enum variants from a type alias with use chrono::LocalResult::*.

We have two choices:

• revert the rename entirely for the 0.4.x versions.
• change the enum definition to be on LocalResult, and use the type alias everywhere else.

The second choice has my preference. The docs look mostly sane, but break down once you come to the trait implementations section:

...

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 91.82%. Comparing base (ca3c3b6) to head (19dd217).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #1547 +/- ## ======================================= Coverage 91.82% 91.82% ======================================= Files 40 40 Lines 18345 18345 ======================================= Hits 16846 16846 Misses 1499 1499 ```

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[pitdicker]

Published.

I'll look through the rust issue tracker if there is anything about type aliases for enums.

[pitdicker]

Opened https://github.com/rust-lang/rust/issues/123131.