No worries here, those are simply informational notices created by WordPress. The DB table engine for the tables used Connections do not support FULLTEXT search indexes. Connection will fallback to a simpler/less accurate search routine in this case.
My guess why you’re, specifically, saw these notices during the update is that you have an older install of Connections … older meaning initially installed a year or two ago. Newer installs, this is properly detected at the initial install and will create the tables with the correct table engine to support FULLTEXT indexes. Older installs, when the tables were created, it just used whatever default table db engine the web host defined as the default.
Any way… probably more than you wanted to know, but I hope it helps.