.builds: remove unused path from PATH

It was left over from when the builds didn't use the distro version
of Go.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

.builds/linux.yml

@@ -12,7 +12,7 @@ packages:
 sources:
  - https://git.sr.ht/~eliasnaur/gio
 environment:
- PATH: $PATH:/usr/bin:/home/build/goroot/go/bin
+ PATH: $PATH:/usr/bin
 tasks:
  - install_chrome: |
      curl -s https://dl.google.com/linux/linux_signing_key.pub | sudo apt-key add -