Removed duplication of bin on obj folders

These two lines look like a duplicate of what we already have at the top of the
file and if we want to keep it should probably go under # Build results

CSharp.gitignore

@@ -89,8 +89,6 @@ csx
 AppPackages/
 
 # Others
-[Bb]in
-[Oo]bj
 sql
 TestResults
 [Tt]est[Rr]esult*