Swagger: Add information to API Token header (#7585)

* Add a description to the API Token header for swagger

routers/api/v1/api.go

@@ -43,6 +43,7 @@
 //          type: apiKey
 //          name: Authorization
 //          in: header
+//          description: API tokens must be prepended with "token" followed by a space.
 //     SudoParam:
 //          type: apiKey
 //          name: sudo

templates/swagger/v1_json.tmpl

@@ -10390,6 +10390,7 @@
       "in": "query"
     },
     "AuthorizationHeaderToken": {
+      "description": "API tokens must be prepended with \"token\" followed by a space.",
       "type": "apiKey",
       "name": "Authorization",
       "in": "header"