New Blazor querystring building APIs.

[MackinnonBuck]

New Blazor querystring building APIs.
Added new APIs for building URLs with querystrings from one or multiple parameter names and values.

PR Description
I've added all three APIs documented here. The current implementation doesn't make a massive effort to avoid allocations, but that is something I've been investigating along the way. If we deem it unnecessary to optimize further, I'm fine with the implementation strategy currently in place.

Addresses #34115

[ghost]

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[pranavkm]

Weird you had to do DisallowNull. Is that part of the signature?

[MackinnonBuck]

This implementation was pulled out of QueryParameterValueSupplier.cs, but also I implemented my own comparer before doing that, and iirc it auto generated the DisallowNull attribute. Found this discussion about it: dotnet/runtime#30998.

[MackinnonBuck]

Another thing - there isn't implemented support for having IEnumerable<T> values for UriWithQueryParameters (the one that accepts an IReadOnlyDictionary<string, object> for parameter assignments). Thoughts about whether this is something worth having?

[SteveSandersonMS]

If it doesn’t blow up the complexity of implementation to support adding multi-valued parameters as part of a dictionary, I think it would be beneficial. Do you think it would work out?

[MackinnonBuck]

@SteveSandersonMS I've just added support for multi-valued parameters in UriWithQueryParameters. It required a bit of finessing but it thankfully didn't blow up the complexity.

[SteveSandersonMS]

This looks awesome! I think you've done a great job of making such a large number of overloads manageable, and came up with some great abstractions to simplify the shared code in an efficient way.

[SteveSandersonMS]

/azp run

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