bugfix(MAPEX-204): Update mapex code to generate valid STIX and check…

… validity with a STIX validator

* bugfix(MAPEX-204): update mapex code to generate valid STIX and check validity with a STIX validator

* ensure stix types match IDs, add stix validation to pipeline

* bugfix(MAPEX-204): update tests to reflect new stix bundle

* build base for generating website

* bugfix(MAPEX-204): handle non mappable nist objects, add standardized date to mappings

* bugfix(MAPEX-204) do not reference mapping_type, fail build if error with stix bundles

* fix error with relationships mapping to other relationships

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Co-authored-by: arobbins <[email protected]>