SQL csharp template minor improvements

[dzsquared]

@Charles-Gagnon @lucyzhang929

• fixes namespace input not being passed into templates
• corrects errant space in input and output templates
• makes output binding a bit more robust with post body

[net-foundation-cla[bot]]

Thank you for your submission, we really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.

:x: dzsquared sign now
_{You have signed the CLA already but the status is still pending? Let us recheck it.}