testing: convert asn_lint_exceptions.json to asn_config.json

Add new child fields to asn_config.json's "asn_files" field object values:
  lint_exceptions:
	List of lint warnings to ignore.
	This replaces asn_lint_exceptions.json.

I.e., ["asn_files"][path]["lint_exceptions"] = list(warningsString)

All of the ASN.1 parsing configuration is now in asn_config.json.