[BUG][go] ST1005 when running staticcheck on generated client code

Created by: maelick

Bug Report Checklist

Description

When running staticcheck on the generated go client, there are several ST1005 errors.

openapi-generator version

Using openapitools/openapi-generator-cli:v6.1.0 but the problem persists in the mustache templates of latest master.

OpenAPI declaration file content or url

openapi: "3.0.3"
info:
  version: 1.0.0
  title: test
paths:
  /endpoint:
    get:
      responses:
        200:
          description: 'successful operation'
          content:
            application/json:
              schema:
                type: array
                items:
                  type: string

Generation Details

docker run --rm -v $(pwd):/local openapitools/openapi-generator-cli:v6.1.0 generate -i local/api.yaml -g go -o local/client --additional-properties=outputAsLibrary=true

Steps to reproduce

Run staticcheck on the generated code:

go install honnef.co/go/tools/cmd/staticcheck@2022.1
cd client
staticcheck .

Related issues/PRs

I didn't find any issue/PR mentioning ST1005.

Suggest a fix

Update the mustache templates that do not follow the code style guidelines for fmt.Errorf.