Improve error when nonhierarchical rel can't be looked up due to wrong documenttype

[kspurgin]

For example, I created by NHR ingest csv with objectexits instead of the correct objectexit, and got this mess, instead of anything relevant to how to actually fix the problem:

❯  thor batch map nhr
Success: CSID cache cleared
Success: REFNAME cache cleared
Analyzing nonhierarchicalrelationship source CSV for record types to csid-cache...
DEBUGGER: Attaching after process 26345 fork to child process 26365
Elapsed time: 0.06114
/Users/kristina/code/cs/migration_tools/lib/collectionspace_migration_tools/batch/csid_cache_dependency_identifier.rb:62:in `sort': comparison of String with nil failed (ArgumentError)
	from /Users/kristina/code/cs/migration_tools/lib/collectionspace_migration_tools/batch/csid_cache_dependency_identifier.rb:62:in `analyze_nonhierarchicalrelationship'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/dry-monads-1.5.0/lib/dry/monads/do.rb:131:in `block in analyze_nonhierarchicalrelationship'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/dry-monads-1.5.0/lib/dry/monads/do/mixin.rb:40:in `call'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/dry-monads-1.5.0/lib/dry/monads/do.rb:131:in `analyze_nonhierarchicalrelationship'
	from /Users/kristina/code/cs/migration_tools/lib/collectionspace_migration_tools/batch/csid_cache_dependency_identifier.rb:33:in `call'
	from /Users/kristina/code/cs/migration_tools/lib/collectionspace_migration_tools/batch/csid_cache_dependency_identifier.rb:14:in `call'
	from /Users/kristina/code/cs/migration_tools/lib/collectionspace_migration_tools/batch/autocache_runner.rb:24:in `call'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/dry-monads-1.5.0/lib/dry/monads/do.rb:131:in `block in call'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/dry-monads-1.5.0/lib/dry/monads/do/mixin.rb:40:in `call'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/dry-monads-1.5.0/lib/dry/monads/do.rb:131:in `call'
	from /Users/kristina/code/cs/migration_tools/lib/collectionspace_migration_tools/batch/autocache_runner.rb:12:in `call'
	from /Users/kristina/code/cs/migration_tools/lib/collectionspace_migration_tools/batch/map_runner.rb:35:in `call'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/dry-monads-1.5.0/lib/dry/monads/do.rb:131:in `block in call'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/dry-monads-1.5.0/lib/dry/monads/do/mixin.rb:40:in `call'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/dry-monads-1.5.0/lib/dry/monads/do.rb:131:in `call'
	from /Users/kristina/code/cs/migration_tools/lib/collectionspace_migration_tools/batch/map_runner.rb:15:in `call'
	from /Users/kristina/code/cs/migration_tools/lib/collectionspace_migration_tools/batch.rb:36:in `map'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/dry-monads-1.5.0/lib/dry/monads/do.rb:131:in `block in map'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/dry-monads-1.5.0/lib/dry/monads/do/mixin.rb:40:in `call'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/dry-monads-1.5.0/lib/dry/monads/do.rb:131:in `map'
	from /Users/kristina/code/cs/migration_tools/lib/tasks/batch.thor:68:in `map'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.2.1/lib/thor/command.rb:27:in `run'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-hollaback-0.2.1/lib/thor/hollaback.rb:68:in `run'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.2.1/lib/thor/invocation.rb:127:in `invoke_command'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.2.1/lib/thor.rb:392:in `dispatch'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.2.1/lib/thor/base.rb:485:in `start'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.2.1/lib/thor/runner.rb:43:in `method_missing'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.2.1/lib/thor/command.rb:29:in `run'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.2.1/lib/thor/command.rb:135:in `run'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.2.1/lib/thor/invocation.rb:127:in `invoke_command'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.2.1/lib/thor.rb:392:in `dispatch'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.2.1/lib/thor/base.rb:485:in `start'
	from /Users/kristina/.rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.2.1/bin/thor:6:in `<top (required)>'
	from /Users/kristina/.rbenv/versions/3.1.0/bin/thor:25:in `load'
	from /Users/kristina/.rbenv/versions/3.1.0/bin/thor:25:in `<main>'