[#41]: Streamline signing for CoRIM protected header + test both routes

[iadgovuser62]

There are 2 typical routes of actions for RIMs in this tool:

1. Create (unsigned) > Sign > Verify
2. Create (signed) > Verify

Currently for CoRIM, these 2 routes differ greatly and the codeflow is different for Create (unsigned) versus Create (signed). Specifically, the Create (signed) code adds fields to the protected header (i.e. corim-meta-map) which the current IETF spec requires (see section 4.2.1). Objects with these additions from the Create (signed) route are failing to verify.

This PR is intended to:

• Unify CoRIM's code for Create (unsigned) and Create (signed), while maintaining additional fields for CoRIM (i.e. corim-meta-map)
• Add respective tests to the corim_comid_tests.sh script to test both routes
• Point to an updated HIRS main branch to use as submodule, now that [RIM-Tool #41]: Modify CoRIM signing for RIM-Tool bugfix HIRS#1173 is merged

To test, run src/test/scripts/corim_comid_tests.sh, or run_all_tests.sh if desired.

Resolves #41