Fix generated json schema with index signature in "instances"

Author: wandamora

schema/firebase-config.json

@@ -928,8 +928,11 @@
                     "type": "array"
                 },
                 "instances": {
-                    "$ref": "#/definitions/Record<string,string>",
-                    "description": "Dictionary mapping instance IDs to their configuration directories"
+                    "additionalProperties": {
+                        "type": "string"
+                    },
+                    "description": "Dictionary mapping instance IDs to their configuration directories",
+                    "type": "object"
                 },
                 "kit": {
                     "description": "Unique identifier for the functions kit (peer to codebase)",

src/firebaseConfig.ts

@@ -201,7 +201,8 @@ export type KitFunctionConfig = FunctionConfigBase & {
   /** Local directory containing the kit source code. */
   source: string;
   /** Dictionary mapping instance IDs to their configuration directories */
-  instances: Record<string, string>;
+  // eslint-disable-next-line @typescript-eslint/ban-types
+  instances: { [instanceId: string]: string };
   /** codebase cannot be used in a kit stanza */
   codebase?: never;
   /** remoteSource cannot be used in a kit stanza */