Trim kibana url madness

Remove all unnecessary elements of the obviously-named "_a" parameter,
from "fullScreenMode" until the end of the query string.

The parameter itself is an nested hash in the format (key:value, ...).
2 jobs for kibana-url in 42 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
passed #4424
build

00:00:26

 
  Docker Build
passed #4425
docker_build

00:00:16