Read Audit implementation from MorphMany

[gisostallenberg]

To allow a different Audit implementation per model the implementation should be deducted from the MorphMany given by the Auditable::audits method.

This will allow having a main Audit implementation (which defaults to OwenIt\Auditing\Models\Audit), but also have a different implementation once the Auditable::audits method is overwritten.

Example:

class MyAuditable extends Model implements AuditableContract
{
    use Auditable;

    /**
     * @return MorphMany<AuditOfMyAuditableModel>
     */
    public function audits(): MorphMany
    {
        return $this->morphMany(
            AuditOfMyAuditableModel::class,
            'auditable',
        );
    }

[MortenDHansen]

It is a good idea! - I do need some test coverage of the feature though.

[erikn69]

Fix on a08c673