- move trimming defaultUsername inside the if-branch, as it's the only
location where the result of the trimmed username is use.
- do the reverse for trimming argUser, because the result of trimming
argUser is used outside of the if-branch (not just for the condition).
putting it inside the condition makes it easy to assume the result is
only used locally.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>