[Golang] Build error (undefined: os) when using generated golang client SDK

Description

Missing import when a model's property is an array/map of file
https://swagger.io/specification/v2/#:~:text=Model%20with%20Map/Dictionary%20Properties

Swagger-codegen version

3.0.34, 3.0.34

Swagger declaration file content or url

https://gist.githubusercontent.com/Masato516/ae52739d1dfd79a37edabe7375319df6/raw/5cef0fb8fe3a9664b51646845e1aca295314c155/vuls-sample.yaml

Command line used for generation

swagger-codegen generate -i https://gist.githubusercontent.com/Masato516/ae52739d1dfd79a37edabe7375319df6/raw/5cef0fb8fe3a9664b51646845e1aca295314c155/vuls-sample.yaml -l go -o ~/project/swagger-codegen/go/out/

Steps to reproduce

go run the below main.go (Due to a build error, the content of the code is not relevant to the problem.)

package main

import (
	"fmt"

	sw "localpackages/swagger"
)

func main() {
	configuration := sw.NewConfiguration()
	apiClient := sw.NewAPIClient(configuration)
	fmt.Println(apiClient)
}

output

Build Error: go build -o /Users/masato/project/swagger-codegen/go/example/api/__debug_bin -gcflags all=-N -l .
# localpackages/swagger
../swagger/model_task_get_task_detail_response_body.go:26:19: undefined: os (exit status 2)

Related issues/PRs

I reported a similar problem on the Openapi-generator that forked Swagger-codegen and got it fixed
https://github.com/OpenAPITools/openapi-generator/pull/13143

Suggest a fix/enhancement

The following PR from the openapi-generator may be helpful in solving the problem.
https://github.com/OpenAPITools/openapi-generator/pull/13143

Start by reproducing the issue with the provided vuls-sample.yaml and the swagger-codegen generate ... -l go command. Inspect the generated model_task_get_task_detail_response_body.go file and compare the missing import behavior with the referenced OpenAPI Generator PR. Done means the generated Go SDK builds and the example main.go runs without the undefined os error.