Allow overriding default implementation of TemporaryDirectory

[jonerickson]

This PR arises out of the need to change the default implementation of the TemporaryDirectory service. In our story, serving a multi-tenant application and using this package to backup each individual tenant's DB, we needed the ability to customize the temporary directory's location. Because we have a large number of tenants, we elected to create a batch job to backup each tenant's DB. Because of this, we are running into the issue where multiple jobs are trying to use the same temporary directory. As you can imagine, this creates chaos. We now have the ability to set the file path based on the current tenant context allowing each tenant to use their own temporary directory.

Extending the implementation:

$this->app->extend(TemporaryDirectory::class, function () {
    return new TenantTemporaryDirectory();
});

Customizing our tmp path:

class TenantTemporaryDirectory extends TemporaryDirectory implements TemporaryDirectoryContract
{
    protected function getFullPath(): string
    {
        $tenantId = tenant()->getTenantKey();

        return storage_path(optional($tenantId, fn ($id) => "app/backup-temp/tenant$id") ?? 'app/backup-temp').DIRECTORY_SEPARATOR.$this->name;
    }
}

[jonerickson]

Hey Spatie team, seeing if you have any questions regarding this PR. Thanks!