Remove unused public function connection on stores which where also not covered by an interface

Author: DanielBadura

src/Store/StreamDoctrineDbalStore.php

@@ -523,11 +523,6 @@ public function setupSubscription(): void
         ));
     }
 
-    public function connection(): Connection
-    {
-        return $this->connection;
-    }
-
     private function createTriggerFunctionName(): string
     {
         $tableConfig = explode('.', $this->config['table_name']);

src/Store/TaggableDoctrineDbalStore.php

@@ -713,11 +713,6 @@ public function setupSubscription(): void
         ));
     }
 
-    public function connection(): Connection
-    {
-        return $this->connection;
-    }
-
     private function createTriggerFunctionName(): string
     {
         $tableConfig = explode('.', $this->config['table_name']);