docs: mark `NC_INVITE_ONLY_SIGNUP` as removed

re #4708

Signed-off-by: Pranav C <pranavxc@gmail.com>

packages/noco-docs/content/en/getting-started/installation.md

@@ -465,7 +465,7 @@ It is mandatory to configure `NC_DB` environment variables for production usecas
 | NC_PUBLIC_URL                      | Yes       | Used for sending Email invitations                                                                                      | Best guess from http request params                                                            |   |
 | NC_JWT_EXPIRES_IN                  | No        | JWT token expiry time                                                                                                   | `10h`                                                                                          |   |
 | NC_CONNECT_TO_EXTERNAL_DB_DISABLED | No        | Disable Project creation with external database                                                                         |                                                                                                |   |
-| NC_INVITE_ONLY_SIGNUP              | No        | Allow users to signup only via invite url, value should be any non-empty string.                                        |                                                                                                |   |
+| NC_INVITE_ONLY_SIGNUP              | No        | <strong>Removed</strong> since version <kbd>0.99.0</kbd> and now it's recommended to use [super admin settings menu](/setup-and-usages/account-settings#enable--disable-signup). <br><br>Allow users to signup only via invite url, value should be any non-empty string.                                        |                                                                                                |   |
 | NUXT_PUBLIC_NC_BACKEND_URL         | No        | Custom Backend URL                                                                                                      | ``http://localhost:8080`` will be used                                                         |   |
 | NC_REQUEST_BODY_SIZE               | No        | Request body size [limit](https://expressjs.com/en/resources/middleware/body-parser.html#limit)                         | `1048576`                                                                                      |   |
 | NC_EXPORT_MAX_TIMEOUT              | No        | After NC_EXPORT_MAX_TIMEOUT csv gets downloaded in batches                                                              | Default value 5000(in millisecond) will be used                                                |   |