gql.tada doctor/check cannot handle headers in schema object

[KammererTob]

Describe the bug

gql.tada CLI commands which parse the config containing headers in the schema object fail (examples are doctor and check).

Reproduction:

1. New Project with those two files. package.json:

   {
   "name": "gql-tada-bug",
   "version": "1.0.0",
   "main": "index.js",
   "license": "MIT",
   "dependencies": {
   "gql.tada": "^1.5.1",
   "typescript": "^5.4.5"
   },
   "devDependencies": {
   "@0no-co/graphqlsp": "^1.10.1"
   }
   }

   tsconfig.json (copied from the documentation):

   {
   "compilerOptions": {
   "plugins": [ 
     {
       "name": "@0no-co/graphqlsp",
       "schema": {
         "url": "http://localhost:4321/graphql",
         "headers": {
           "Accept": "application/graphql-response+json"
         }
       }
     }
   ]
   }
   }

2. yarn / npm install
3. gql.tada doctor

Leads to the following error:

⚠ Error The plugin configuration for "@0no-co/graphqlsp" seems to be invalid. ┗ Configuration contains a schema.headers property, but it's not an object

Reproduction

No response

gql.tada version

gql.tada v1.5.1

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