docker: allow running 1_base/build.sh with --no-cache

This rebuilds the image from scratch, also pulling in security updates.

docker/1_base/build.sh

@@ -1,3 +1,3 @@
 #!/usr/bin/env bash
 
-exec docker build -t pillar_base -f base.docker .
+exec docker build "$@" -t pillar_base -f base.docker .