Apply changes when creating invoices for projects.

app/Models/Invoice.php

@@ -43,25 +43,6 @@ class Invoice extends Model
         'localized_state'
     ];
 
-    /**
-     * Set the project_count variable automatically, if a project is related to this invoice.
-     */
-    public static function boot(): void
-    {
-        parent::boot();
-        self::creating(function (Invoice $invoice) {
-            if (is_null($invoice->project_id)) {
-                return true;
-            }
-            if ($invoice->type != '326') {
-                return true;
-            }
-            $projectMax = Invoice::where('project_id', '=', $invoice->project_id)->max('project_count') + 1;
-            $invoice->project_count = $projectMax;
-            return true;
-        });
-    }
-
     /**
      * Get the invoice state as translated string.
      */