Serialized parameters named "collection" cannot be accessed in NREP

[FifthPotato]

Bug Report

While implementing #7668, I noticed that a parameter named collection seemed to have special meaning in the NREP. If any serialized parameter is named collection is accessed, it appears to create an un-resolvable type error in the NREP.

iRODS Version, OS and Version

4.3.1, ubuntu20

What did you try to do?

I attempted to add an entry into a serialization map with key collection and then access it in a relevant pep e.g.

pep_api_struct_file_ext_and_reg_post(*INSTANCE, *COMM, *STRUCTINP) {
                *v = *STRUCTINP.collection;
}

Note that to work around this, I instead named the key collection_path. I do not know if this is a weird one-off for this struct alone, or if this is global behavior for any key named collection.

Expected behavior

It works without error and *v is set to the appropriate value.

Observed behavior (including steps to reproduce, if applicable)

The logs report an unresolvable typing constraint and the rule fails to run.