fixing trailing errors for golang lint

[mrtrkmn]

There are bunch of errors and warnings when we run linting for the project, could be nice that we have linting in CI process and obey the rules of it. Here is a screenshot from the results of running following command in root directory of the project.

curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s v1.24.0
./bin/golangci-lint run -D errcheck

Some parts of errors :

I have added them into github actions test workflow, however I did not enable it, once the issues regarding to this command has been fixed, we can re-enable it along the way.

It is open to discussion that whether should we have a linting mechanism or not, do not hesitate to discuss below by sharing your opinion.