added alert .sh files and library files to support alerting

2 jobs from master in 7 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Build
failed #8370
ci
build_job

00:00:07

 
  Deploy
skipped #8371
cd
deploy_job
 
Name Stage Failure
failed
build_job Build
./panels_common.jsonnet
panels_common
./alerts/alert_rule.jsonnet
alert_rule
RUNTIME ERROR: couldn't open import "grafonnet-lib/grafonnet/alerts/alert_rule.libsonnet": no match locally or in the Jsonnet library paths.
./alerts/alert_rule.jsonnet:1:20-80 thunk <alert_test>
./alerts/alert_rule.jsonnet:28:1-11
Cleaning up project directory and file based variables
ERROR: Job failed: exit status 1