Remove obsolete SDF URNs

[damccorm]

We currently only use PAIR_WITH_RESTRICTION, SPLIT_AND_SIZE_RESTRICTIONS, and PROCESS_SIZED_ELEMENTS_AND_RESTRICTIONS. We should remove PROCESS_KEYED_ELEMENTS and probably remove PROCESS_ELEMENTS and SPLIT_RESTRICTION as well.

Imported from Jira BEAM-9272. Original Jira may contain additional context.
Reported by: robertwb.