Should we ignore query param in the cache key for sitemaps

[owaincuvelier]

Sitemaps can be a real performance issue for sites, particularly large ones. One of the main ways to offset the performance of sitemaps is pregenerate and/or to cache the sitemaps. Unless we ignore query params to sitemaps, it would be very easy to take sites down.

Perhaps this is already being done and I'm not aware?

[wisyhambolu]

This looks like a duplicate of humanmade/altis-documentation#659, closing to focus on humanmade/altis-documentation#659