C# - nullable string

[gbmarc1]

Make string a nullable type.

Useful for optional query param

#9233

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[gbmarc1]

Mentioning technical committee
@mandrean @frankyjuang @shibayan @Blackclaws

[devhl-labs]

I think it requires a bit more than what you've changed. I added an option for NRT here #9235. I don't mean to swoop in right after your pr, but I started this work a few weeks ago and was asked to split the option out from other work. Just took time to get to it.

[gbmarc1]

@devhl-labs Do you think it would be better for me to work on this PR after your's is completed?

[devhl-labs]

Yes, of course. Or you can clone my branch and see if it helps fix your problem.

[wing328]

Closed per #9234 (comment)