Remove usage of getenv=True in HTCondor .sub files

IGWN Computing is beginning to phase out support for getenv = True in HTCondor submit files (see computing&30 and links therein). This is a good idea in general, as it can and has led to confusing inconsistencies in runs between different users or even for the same user. The downside is that we have to actually know which environment variables we need set, and to do that explicitly within RapidPE. Best practices are documented in the IGWN computing docs. We currently use this in dagutils.py in the following locations:

• ILE jobs
• SQL jobs
  • NOTE: I think this isn't actually used anymore, should be safe to just remove
• Plot jobs: [1] [2] [3] [4]