Add attachment to recurring.

app/Models/Recurrence.php

@@ -189,6 +189,15 @@ class Recurrence extends Model
         return $this->belongsTo(TransactionCurrency::class);
     }
 
+    /**
+     * @codeCoverageIgnore
+     * @return MorphMany
+     */
+    public function attachments(): MorphMany
+    {
+        return $this->morphMany(Attachment::class, 'attachable');
+    }
+
     /**
      * @codeCoverageIgnore
      * @return BelongsTo