* enable Litmus Smoke tests on daily PRs
- created a litmus_daily job
- added persist_to_workspace to build job to have access to influxd binary
- added litmus_daily to build workflow
- added two script files, litmus_success_notify.sh and litmus_fail_notify.sh to `etc` directory
- added the above script files to the one to be shared in the workspace
- updated litmus_daily and litmus_nightly jobs to use scripts for notifications.