fix: Add CAA record type to DNS enum classes to support custom domain operations

This commit resolves a critical validation error that caused 5 out of 6 custom
domain API endpoints to fail when the Okta API returned CAA (Certificate Authority
Authorization) DNS records.

Problem:
- DNSRecordTypeDomains and EmailDomainDNSRecordType enums only defined CNAME and TXT
- When API returned CAA records, Pydantic validation failed during deserialization

Solution:
Added CAA record type to both enum classes:
- okta/models/dns_record_type_domains.py
- okta/models/email_domain_dns_record_type.py

Testing:
Verified with get_custom_domain() method that CAA records now deserialize correctly without validation errors.

Author: BinoyOza-okta

okta/models/dns_record_type_domains.py

@@ -38,6 +38,7 @@ class DNSRecordTypeDomains(str, Enum):
     """
     CNAME = "CNAME"
     TXT = "TXT"
+    CAA = "CAA"
 
     @classmethod
     def from_json(cls, json_str: str) -> Self:

okta/models/email_domain_dns_record_type.py

@@ -38,6 +38,7 @@ class EmailDomainDNSRecordType(str, Enum):
     """
     CNAME = "CNAME"
     TXT = "TXT"
+    CAA = "CAA"
 
     @classmethod
     def from_json(cls, json_str: str) -> Self:

openapi/api.yaml

@@ -63370,6 +63370,7 @@ components:
       enum:
         - CNAME
         - TXT
+        - CAA
     DRStatusItem:
       description: Status whether a domain has been failed over or not
       type: object
@@ -64698,6 +64699,7 @@ components:
       enum:
         - CNAME
         - TXT
+        - CAA
     EmailDomainResponse:
       allOf:
         - $ref: '#/components/schemas/BaseEmailDomain'