Change dependency pdsinterop/flysystem-rdf from v0.3 to v0.4.

Author: Potherca

composer.json

@@ -22,7 +22,7 @@
     "laminas/laminas-diactoros": "^2.8",
     "league/flysystem": "^1.0",
     "mjrider/flysystem-factory": "^0.5",
-    "pdsinterop/flysystem-rdf": "^0.3",
+    "pdsinterop/flysystem-rdf": "^0.4",
     "psr/http-factory": "^1.0",
     "psr/http-message": "^1.0",
     "textalk/websocket": "^1.5"