Drop DBAL 2 support (#63)

DBAL 2 is no longer maintained since around October 2022.

Author: mpdude

composer.json

@@ -16,7 +16,7 @@
 
     "require": {
         "php": ">= 8.1",
-        "doctrine/dbal": "^2.13|^3.0",
+        "doctrine/dbal": "^3.0",
         "doctrine/orm": "^2.8|^3.0",
         "doctrine/persistence": "^2.1|^3.0",
         "psr/container": "^1.0",