more unique ID generation to prevent multiple attachments with same ID (Webklex#363)

Author: Guite

src/Attachment.php

@@ -202,7 +202,7 @@ protected function fetch(): void {
         if (($id = $this->part->id) !== null) {
             $this->id = str_replace(['<', '>'], '', $id);
         }else{
-            $this->id = hash("sha256", (string)microtime(true));
+            $this->id = hash("sha256", uniqid((string) rand(10000, 99999), true));
         }
 
         $this->size = $this->part->bytes;
@@ -339,4 +339,4 @@ public function mask(string $mask = null): mixed {
 
         throw new MaskNotFoundException("Unknown mask provided: ".$mask);
     }
-}
+}