Not all `operationHeaders` are forwarded

[Kerem Kambur]

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• 1. The issue provides a reproduction available on
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  Stackblitz
  or
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Make sure to fork this template and run yarn generate in the terminal.

Please make sure Mesh package versions under package.json matches yours.

• 2. A failing test has been provided
• 3. A local solution has been provided
• 4. A pull request is pending review

---

Describe the bug

I recently needed to forward a new custom header by listing it under the operationHeaders section in configuration file.

To Reproduce Steps to reproduce the behavior:

It's basically nothing special, I just added a new header in configuration file. Here is the meshrc.yaml

sources:
  - name: CmsApi
    handler:
      graphql:
        endpoint: ${SOME_BASE_URL}/graphql
        operationHeaders:
          "x-app-name": "{context.headers['x-app-name']}"
          "x-app-platform": "{context.headers['x-app-platform']}"

  - name: UserApi
    handler:
      graphql:
        endpoint: ${ANOTHER_GQL_API}/graphql
        operationHeaders:
          Authorization: "{context.headers.authorization}"
          "auth-provider": "{context.headers['auth-provider']}"
          "x-app-name": "{context.headers['x-app-name']}"
          "x-app-platform": "{context.headers['x-app-platform']}"
          
  - name: XdrApi
    handler:
      jsonSchema:
        endpoint: ${XDR_API_BASE_URL}
        operations:
          - type: Query
            field: xdrData
            path: /xdr/playhead/account/{args.someArg}/{args.someArg2}
            method: GET
            responseSchema: ./xdr/json-schemas/playheadData.json
            # responseTypeName: xdrData

codegen:
  #Default values can be found here https://the-guild.dev/graphql/mesh/docs/guides/graphql-code-generator
  skipTypename: true
  flattenGeneratedTypes: false
  onlyOperationTypes: false
  preResolveTypes: false
  namingConvention: keep
  documentMode: graphQLTag
  gqlImport: "@graphql-mesh/utils#gql"
  enumsAsTypes: true
  ignoreEnumValuesFromSchema: true
  useIndexSignature: true
  contextType: MeshContext

And below is what I got on server side

Expected behavior

Obtaining the defined new x-app-platform value.

Environment:

• OS: Cloudflare Worker
• @graphql-mesh/...: "@graphql-mesh/graphql": "^0.95.2"
• NodeJS:

Additional context