Reference docs for kubernetes 1.23

content/en/docs/reference/kubernetes-api/common-definitions/node-selector-requirement.md

@@ -37,6 +37,14 @@ A node selector requirement is a selector that contains values, a key, and an op
 - **operator** (string), required
 
   Represents a key's relationship to a set of values. Valid operators are In, NotIn, Exists, DoesNotExist. Gt, and Lt.
+  
+  Possible enum values:
+   - `"DoesNotExist"`
+   - `"Exists"`
+   - `"Gt"`
+   - `"In"`
+   - `"Lt"`
+   - `"NotIn"`
 
 - **values** ([]string)