Reorganize general / reused functions

[Joshdpaul]

There are some functions that are used across different flows, with only slight modifications in each use case:

• check_for_nfs_mount()
• clone_github_repository()
• install_conda_environment()
• get_job_ids()
• wait_for_jobs_completion()

These should be collected together (e.g. in aprefect_utilities.py script) where we can call and reuse them. Any updates to these basic functions would then be used by all flows, instead of updating each individually.