update common fields for IPv6

Author: terence1988

src/connections/spec/common.md

@@ -203,8 +203,8 @@ Other libraries only collect `context.library`, any other context variables must
 | timezone                 | ✅            | ✅             | ✅                 |
 
 - IP Address isn't collected by Segment's libraries, but is instead filled in by Segment's servers when it receives a message for **client side events only**.
-> info "IPv6 Addresses are not Supported"
-> Segment does not support collection of IP addresses that are in the IPv6 format.
+> info "IPv6"
+> At the moment, Segment doesn't support automatically collecting IPv6 addresses.
   
 - The Android library collects `screen.density` with [this method](/docs/connections/spec/common/#context-fields-automatically-collected).