Sort attributes in HTML nodes when rendering

[MaxDesiatov]

This makes attributes order deterministic and allows testing against HTML renderer output, while currently attributes order is random.

Benchmarks results:

name                            time            std        iterations
---------------------------------------------------------------------
render Text                         9667.000 ns ±   4.35 %     145213
render App unsorted attributes     51917.000 ns ±   4.23 %      26835
render App sorted attributes       52375.000 ns ±   1.62 %      26612
render List unsorted attributes 34546833.500 ns ±   0.79 %         40
render List sorted attributes   34620000.500 ns ±   0.69 %         40

Looks like on average there's ~0.2% difference in performance. I was leaning towards enabling sorting by default, but we're benchmarking here only with short attribute dictionaries, I wonder if the difference could become prominent for elements with more attributes. I kept sorting disabled by default after all, but still configurable.

var html: String on StaticHTMLRenderer was changed to func render(shouldSortAttributes: Bool = false) -> String to allow configuring this directly.

[MaxDesiatov]

I'm going to keep this open, I want to make this configurable on the renderer, so that it doesn't have any performance impact.