Release 1.8.0 · LLNL/merlin

retry_delay field in a step to specify a countdown in seconds prior to running a
restart or retry.
New merlin example restart_delay that demonstrates usage of this feature.
Condition failure reporting, to give greater insight into what caused test failure.
New fields in config file: celery.omit_queue_tag and celery.queue_tag, for
users who wish to have complete control over their queue names. This is a feature
of the task priority change.

feature_demo now uses merlin-spellbook instead of its own scripts.
Removed the --mpi=none srun default launch argument. This can be added by
setting the launch_args argument in the batch section in the spec.
Merlin CI is now handled by Github Actions.
Certain tests and source code have been refactored to abide by Flake8 conventions.
Reorganized the tests module. Made unit dir alongside integration dir. Decomposed
run_tests.py into 3 files with distinct responsibilities. Renamed Condition classes.
Grouped cli tests by sub-category for easier developer interpretation.
Lowered the command line test log level to "ERROR" to reduce spam in --verbose mode.
Now prioritizing workflow tasks over task-expansion tasks, enabling improved
scalability and server stability.
Flake8 examination slightly modified for more generous cyclomatic complexity.
- Certain tests and source code have been refactored to abide by Flake8 conventions.
walltime can be specified in any of hours:minutes:seconds, minutes:seconds or
seconds format and will be correctly translated for the right batch system syntax

For Celery calls, explictly wrapped queue string in quotes for robustness. This fixes
a bug that occurred on tsch but not bash in which square brackets in the queue name were
misinterpreted and caused the command to break.