Incorrect sponsor/missing sponsor on XO Ruby Atlanta

[bigtiger]

XO Ruby Atlanta lists four sponsors. One of them is Cisco Meraki but should be Cisco (https://www.xoruby.com/content/images/size/w2000/format/avif/2025/08/logomark-classic.png).

I also would like to add DNSimple with their new logomark (https://www.xoruby.com/content/images/size/w2000/format/avif/2025/08/logomark-classic.png).

I pulled the repo down locally but was unable to get the Cisco sponsor to recognize anything but the Cisco Meraki sponsor from RubyConf. Similarly the DNSimple sponsor pulled their old logo. I saw @marcoroth had a PR #885 that allows an admin to select which logo they want to use. Maybe it's that's simple?

Let me know how I can help.