Hash sorted args with defaults for RecoFragmentsPool

Merged Teng Jian Khoo requested to merge khoo/athena:RecoFragmentsPool-consistentargs into master

After a couple of bugs with duplicate algs, @jburr and I decided we needed to make RecoFragmentsPool.retrieve more robust. Credit to him for the default arg extraction.

Admittedly I haven't tested this too carefully, leaving this for CI.

Merge request reports