[BUG] Description

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
  Yes
• Have you validated the input using an OpenAPI validator ([example]
  Yes
  (https://apidevtools.org/swagger-parser/online/))?
• What's the version of OpenAPI Generator used?
  openapi-generator-cli:v3.3.4
• Have you search for related issues/PRs?
  Yes, no related issues
• What's the actual output vs expected output?
  Actual:
  package model

type Comp struct {

Files []*os.File `json:"Files,omitempty"`

}

Expected:
package model
import "os"

type Comp struct {

Files []*os.File `json:"Files,omitempty"`

}

• [Optional] Bounty to sponsor the fix (example)

Description

openapi generate for go-gin-server target has issues with the multipart form type specification format: binary

openapi-generator version

openapi-generator-cli:v3.3.4

OpenAPI declaration file content or url

Command line used for generation

  openapitools/openapi-generator-cli:${OPEN_API_VERSION} generate \
  --input-spec /local/${OPEN_API_SPEC} \
  --generator-name ${GENERATOR} \
  --additional-properties=packageName=name \
  --output <>

Steps to reproduce

Related issues/PRs

Suggest a fix

Generate the model code with the import "os" package

Result
package model
import "os"

type Comp struct {

Files []*os.File `json:"Files,omitempty"`

}

Start by reproducing the go-gin-server generation described in the issue with the multipart form property using format: binary, then inspect the generated Comp model. Compare the actual output with the expected import of os; done means the generated Go model includes the required import and remains valid.