Make sure function errors are handled everywhere

[sivachandran]

There are places, e.g., recordStepXXX in service_request_worker.go where function error value is not checked. This would lead to silent errors and would make Clamp unreliable. So, we need to make sure function error values are handled everywhere in the codebase.

golangci-lint identifies function calls without error handling. We should also search for _ := and _ = string in the codebase to identify function calls where the error is explicitly ignored.