Stop adding extra space after tab is pressed

Let's say I'm adding new using to usings section. So I type "usi" and Rider already suggests me that it's gonna be using. Ok, I agree and press tab. So it finishes "using" word itself but also types a space. I expect cursor to stay in the end of the inserted word once I have clicked tab, not an additional space to be inserted. I prefer to click space myself when I want to. 

Could anybody please propose me how to prevent this behavior?