fix(rulesets): use uri-reference for openIdConnectUrl

Similar to #2652 openIdConnectURL can also be a relative reference

Author: johnf

packages/rulesets/src/oas/schemas/oas/v3.1/index.json

@@ -1094,7 +1094,7 @@
             "properties": {
               "openIdConnectUrl": {
                 "type": "string",
-                "format": "uri"
+                "format": "uri-reference"
               }
             },
             "required": ["openIdConnectUrl"]