Document how to specify batch project and runtime
There has been confusion on htcondor-users about how to specify the BatchProject and BatchRuntime added in #6451 (https://www-auth.cs.wisc.edu/lists/htcondor-users/2020-July/msg00118.shtml). We initially told users to "set_remote_BatchRuntime" in their job router but this doesn't appear to result in the appropriate Slurm directives
It turns out that the user had some stale config overriding their JOB_ROUTER_ENTRIES so remote_BatchProject and remote_BatchRuntime are the appropriate attributes to set in the job ad
Since HTCondor 8.7.6, you just need to set BatchProject and BatchRuntime in the job ad.
I will use this ticket as an opportunity to add support in condor_submit for these attributes.