See split glide client classads when using scitokens

[StevenCTimm]

In testing we are seeing that for groups which have two credentials defined
(a scitoken and a grid_proxy) then two glide client classads are created for the group (which serves only one entry).
one of them has both a scitoken and an encoded proxy, the other one has only a scitoken.

If there are a low number of submitted jobs, then the DE can round in such a way that only one of them is used and it
has one chance in two of being the wrong one and not being able to contact the remote htcondor-ce.

This can be mitigated by submitting a lot of jobs and getting glidein requests on both.

[StevenCTimm]

some of this will be handled in the ongoing credential refactoring project within glideinwms that Bruno is working on now.
I am putting this issue in to track it because I discussed this problem with him and we needed to track it