Why this change?
Similar to d0117ff6e32c371822a08a4453f6b0de73c42a0e, `plugins:update_all` spends most of its time waiting
on the network. On my local machine, this takes up to 2 mins when I have
all the official plugins installed. On a 32 cores machine, the total
time is cut down to 4 seconds.
What does this change do?
1. Move the logic in the `plugin:update` Rake task into a method.
2. Updates the `plugin:update` and `plugin:update_all` to rely on the
new method.
3. Wraps the method call to update a plugin in `plugin:update_all` in a
`Concurrent::Promise`
This change also adds the `--quiet` option to the `git pull` option
since the `git pull` output is just noise for 99% of the time.
1e290eed7b