Update manifest.json

bump to 0.3.18

Author: lbbrhzn

custom_components/ocpp/manifest.json

@@ -4,7 +4,7 @@
   "documentation": "https://github.com/lbbrhzn/ocpp/blob/main/README.md",
   "iot_class": "local_push",
   "issue_tracker": "https://github.com/lbbrhzn/ocpp/issues",
-  "version": "0.3.17",
+  "version": "0.3.18",
   "config_flow": true,
   "codeowners": [
     "@lbbrhzn"