You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: testconfig_utils.go
    path of file: ./repos/chainlink/integration-tests/testconfig
    
    the code of the file until where you have to start completion: package testconfig

import (
	"fmt"
	"os"
	"strings"
)

// MissingImageInfoAsError return a helfpul error message when the no Chainlink image info is found in TOML config.
// If legacy env vars are found it prints r
    
func MissingImageInfoAsError(errStr string) error {
	intro := `
Old configuration approach detected. Please use TOML instead of env vars.
Please refer to integration-tests/testconfig/README.md for more information.
`

	var imgStr, versionStr string

	if img := os.Getenv("CHAINLINK_IMAGE"); img != "" {
		imgStr = fmt.Sprintf("image = \"%s\"\n", img)
	}

	if version := os.Getenv("CHAINLINK_VERSION"); version != "" {
		versionStr = fmt.Sprintf("version = \"%s\"\n", version)
	}

	finalErrStr := fmt.Sprintf("%s\n%s", errStr, intro)

	if imgStr != "" && versionStr != "" {
		extraInfo := `
Or if you want to run your tests right now add following content to integration-tests/testconfig/overrides.toml:
[ChainlinkImage]
`
		finalErrStr = fmt.Sprintf("%s\n%s%s%s%s", errStr, intro, extraInfo, imgStr, versionStr)
	}

	return fmt.Errorf(finalErrStr)
}