Pinpoint agent not working for nested jars
#### What version of pinpoint are you using?
1.8.1

#### Describe the bug
There is an exception in the pinpoint agent logs, and it concerns Spring Cassandra library. In fact, Applications that communicate with Cassandra are not linked to each other and I think it's because of this exception.
For example normally the request flow is : 
App 1 > App 2 > Cassandra
but pinpoint web shows it like this : 
App 1
App 2 > Cassandra
So the traceId is lost between the App 1 and App 2

#### Logs
You can see the logs here: https://gist.github.com/simoelmou/7123f75eb341023750daf11675df4284

#### Additional context
I'm using version 1.8.0 for the Collector and Web.