docs: secure attachments

Signed-off-by: mertmit <mertmit99@gmail.com>

packages/noco-docs/versioned_docs/version-0.109.7/020.getting-started/020.environment-variables.md

@@ -62,3 +62,5 @@ For production usecases, it is **recommended** to configure
 | NC_MINIMAL_DBS | Create a new SQLite file for each project. All the db files are stored in `nc_minimal_dbs` folder in current working directory. (This option restricts project creation on external sources) |  |
 | NC_DISABLE_AUDIT | Disable Audit Log | `false` |
 | NC_AUTOMATION_LOG_LEVEL | Possible Values: `OFF`, `ERROR`, `ALL`. See [Webhooks](/developer-resources/webhooks#call-log) for details. | `OFF` |
+| NC_SECURE_ATTACHMENTS | Allow accessing attachments only through presigned urls. To enable secure set value as `true` any other value treated as false. (⚠ this will make existing links inaccessible ⚠) | `false` |
+| NC_ATTACHMENT_EXPIRE_SECONDS | How many seconds before expiring presigned attachment urls. (Attachments will expire in at least set seconds and at most 10mins after set time) | 7200 (2 hours) |