Check current viewport against responsive settings on initial load (fixes #2439)

[John-Youngblood]

This PR adds a manual check against the responsive query when the Slider component initially loads. This will make sure the Slider pulls in any related responsive settings based on the current viewport when it first renders. The responsive.spec.tsx test for playwright was also updated to catch this edge case. It's initial viewport is now one that hits a responsive breakpoint instead of the default. This fixes issue #2439