IPA-126: Top-Level API Names (fix) (#670)

Author: yelizhenden-mdb

tools/spectral/ipa/rulesets/IPA-126.yaml

@@ -33,6 +33,7 @@ rules:
           - 'MongoDB'
           - 'LDAP'
           - 'GCP'
+          - 'OpenAPI'
         grammaticalWords:
           - 'and'
           - 'or'