[SSL] Add note about CAA records completeness

Added a note regarding the completeness of the CAA records list.
PCX-19177

Author: ngayerie

src/content/partials/ssl/caa-records-added-by-cf.mdx

@@ -31,3 +31,7 @@ If Cloudflare has automatically added CAA records on your behalf, these records
 0 issue "sectigo.com"
 0 issuewild "sectigo.com"
 ```
+
+:::note
+Please note that this list is not exhaustive, other CAs might be added or removed for operational reasons.
+:::