Nested sitemap is not processed by Sitemap Extractor

[nicklamonov]

Runs:

• https://console.apify.com/admin/users/LXB1SUPdX8eVlw5mf/actors/rGeTNESChDZ65EbYh/runs/g0m8obTZoJnReuT4R#log
• https://console.apify.com/admin/users/LXB1SUPdX8eVlw5mf/actors/rGeTNESChDZ65EbYh/runs/CpemNfhNsuoW5xych#log
• https://console.apify.com/admin/users/LXB1SUPdX8eVlw5mf/actors/rGeTNESChDZ65EbYh/runs/LBf89OIMbubTRu3sd#log

Current problem:
Main sitemap contains a link to another nested sitemap(s), but they are not parsed.

Expected:
Nested sitemaps are parsed too.