There's no notification handling for connection requests. Meaning the title/message won't dynamically generate and output at time of display based off the status of the connection request. That'll be added in a future build release of CB Activity as noted below.
forge.joomlapolis.com/issues/6950
You can use the below to try and be compatible with the future implementation of this.
Global
Triggers: onAfterAddConnection
Type: CB Activity
User: Automatic
Access: Everybody
Action
Mode: Notification
Method: Create
Asset: profile.[var1].connection.[var2][cb:if var3="1"].pending[/cb:if]
Title: [cb:if var3="1"]has sent you a connection request[/cb:if]
Owner: [var1]
User: [var2]
Date: now
Load: By Asset, Owner, and User
Global
Triggers: onAfterAcceptConnection
Type: CB Activity
User: Automatic
Access: Everybody
Action
Mode: Notification
Method: Create
Asset: profile.[var1].connection.[var2].accepted
Title: has accepted your connection request
Owner: [var1]
User: [var2]
Date: now
Load: By Asset, Owner, and User
Global
Triggers: onAfterDenyConnection
Type: CB Activity
User: Automatic
Access: Everybody
Action
Mode: Notification
Method: Create
Asset: profile.[var1].connection.[var2].rejected
Title: has rejected your connection request
Owner: [var1]
User: [var2]
Date: now
Load: By Asset, Owner, and User
That should handle creating notifications either accepted or pending state. It's likely the core activity parsing will override the title though since that parsing doesn't handle the various states of connection requests at this time. New builds for CB Activity, GJ, and CB Gallery are planned ASAP to improve their notification parsing though. I may have var1 and var2 backwards in either of the above. I don't know at this time as I have yet to test implementation of those notifications.