builder: Don't test for what's not there

(we don't install pip2 anymore, but this may be reverted eventually)

builder/test/tests.sh

@@ -20,8 +20,6 @@ nmap --version
 lsof -v
 git --version
 vim --version
-pip --version
-pip2 --version
 pip3 --version
 tcpdump --version
 monkey --version