Closes #7850: Add note about where to assign FHRP groups

Author: jeremystretch

docs/models/ipam/fhrpgroup.md

@@ -12,3 +12,5 @@ NetBox models these redundancy groups by protocol and group ID. Each group may o
 ## FHRP Group Assignments
 
 Member device and VM interfaces can be assigned to FHRP groups, along with a numeric priority value. For instance, three interfaces, each belonging to a different router, may each be assigned to the same FHRP group to serve a common virtual IP address. Each of these assignments would typically receive a different priority.
+
+Interfaces are assigned to FHRP groups under the interface detail view.