[Infrastructure] Remove Discussions link (#30592)
[Infrastructure] Remove Discussions link (#30592)

Removes the discussions link from the issues tab.

Addresses #30590
aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore,aspnet/AspNetCore