LICENSE and DCO in CODEOWNERS (#2208)

This change adds the LICENSE and DCO files to CODEOWNERS and
specifies the community docs maintainers team as owners.
The purpose of this change is to prevent any unintentional or
unauthorized modifications to these files. Resolves #2178

Author: oraNod

.github/CODEOWNERS

@@ -1,3 +1,6 @@
 /docs/docsite/rst/community/collection_contributors/collection_requirements.rst @ansible/steering-committee
 /docs/docsite/rst/community/steering/* @ansible/steering-committee
 /docs/docsite/rst/roadmap/COLLECTIONS_*.rst @ansible/steering-committee
+# DCO and COPYING need approval from the Red Hat open-source legal team
+/DCO @ansible/community-docs-maintainers
+/COPYING @ansible/community-docs-maintainers