Fix DateRangeSynth hydrate of all time preset

[joshhanley]

The scenario

If a Livewire property is set to a DateRange with a preset of AllTime, then on the next request it fails to hydrate and throws the following error:

<?php

use Livewire\Volt\Component;
use Flux\DateRange;

new class extends Component {
    public DateRange $range;

    public function mount(): void
    {
        $this->range = DateRange::allTime('2018-01-01');
    }
}; ?>

<div class="flex">
    <flux:date-picker wire:model.live="range" mode="range" min="2018-01-01" with-presets/>
</div>

The problem

The issue is that we're not handling the AllTime preset in the hydrate method of DateRangeSynth.

if ($preset) {
    return DateRange::fromPreset(DateRangePreset::from($preset));
}

The solution

This PR adds a check for AllTime and handles it the same way that the hydrateType method does.

if ($preset) {
    if ($preset === DateRangePreset::AllTime->value) {
        return DateRange::allTime($value['start']);
    }

    return DateRange::fromPreset(DateRangePreset::from($preset));
}

Fixes #1160