Deprecated ioutil Package in node_config.go

[s-uryansh]

Hi,
I was going through the code in node_config.go and noticed that it's using the ioutil package, which has been deprecated in Go 1.16. The recommended replacements are:

os.ReadFile instead of ioutil.ReadFile
os.WriteFile instead of ioutil.WriteFile
os.Open instead of ioutil.ReadDir
io.NopCloser instead of ioutil.NopCloser
Updating this will help keep the code more maintainable and compatible with newer Go versions. Let me know if you need any help with the update!