scheduler system test scenarios

more tests
more tests
test for mutiple policies to execute at the same instance
using scheduler_interval
linting
fix lint for real
skipping cron tests
better docstrings
fixed lint
refactor the header validation, setup and using constants
changes fetch url from config for dev and preprod
fixed lint
change to setUp
changes to links test
clean up scripts
changes to server metadata
rand_name reloacted
rand_name reloacted in behaviours too
negative test time.now