[WAF] Leaked credentials: Update fields for custom locations (#17100)

Author: pedrosousa

src/content/docs/waf/detections/leaked-credentials/index.mdx

@@ -72,8 +72,6 @@ Expressions used to specify custom detection locations can include the following
 
 - Fields:
   - [`http.request.body.raw`](/ruleset-engine/rules-language/fields/http-request-body/#httprequestbodyraw)
-  - [`http.request.headers`](/ruleset-engine/rules-language/fields/http-request-header/#httprequestheaders)
-  - [`http.request.uri.query`](/ruleset-engine/rules-language/fields/standard-fields/#httprequesturiquery)
 - Functions:
   - [`lookup_json_string()`](/ruleset-engine/rules-language/functions/#lookup_json_string)
   - [`lower()`](/ruleset-engine/rules-language/functions/#lower)