kafka: doc ability to disable krb FAST (kedacore#1476)

Signed-off-by: John Kyros <[email protected]>

content/docs/2.16/scalers/apache-kafka.md

@@ -100,6 +100,7 @@ partition will be scaled to zero. See the [discussion](https://github.com/kedaco
 - `realm` - Kerberos realm.  (Optional unless sasl mode is `gssapi`)
 - `kerberosConfig` - Kerberos configuration file. (Optional unless sasl mode is `gssapi`)
 - `kerberosServiceName` - Kerberos service name. (Optional takes default value of `kafka` if not provided)
+- `kerberosDisableFAST` - To disable FAST negotation, set this to `true` (Values: `true`, `false`, Default: `false`, Optional)
 - `oauthTokenEndpointUri` - The OAuth Access Token URI used for oauthbearer token requests. (Optional unless sasl mode set to oauthbearer)
 - `scopes` - A comma separated lists of OAuth scopes used in the oauthbearer token requests. (Optional)
 - `oauthExtensions` - A comma separated lists of key value pairs in the format key=value OAuth extensions used in the oauthbearer token. (Optional)